1 John 5:21
Verse
Context
Sermons





Summary
Commentary
- Adam Clarke
- Jamieson-Fausset-Brown
- John Gill
- Tyndale
Adam Clarke Bible Commentary
Little children - Τεκνια· Beloved children; he concludes with the same affectionate feeling with which he commenced. Keep yourselves from idols - Avoid the idolatry of the heathens; not only have no false gods, but have the true God. Have no idols in your houses, none in your churches, none in your hearts. Have no object of idolatrous worship; no pictures, relics, consecrated tapers, wafers, crosses, etc., by attending to which your minds may be divided, and prevented from worshipping the infinite Spirit in spirit and in truth. The apostle, says Dr. Macknight cautioned his disciples against going with the heathens into the temple of their idol gods, to eat of their feasts upon the sacrifices they had offered to these gods; and against being present at any act of worship which they paid them; because, by being present, they participated of that worship, as is plain from what St. Paul has written on the subject, Co1 8:10 (note). That is a man's idol or god from which he seeks his happiness; no matter whether it be Jupiter, Juno, Apollo, Minerva, Venus, or Diana; or pleasure, wealth, fame, a fine house, superb furniture, splendid equipage, medals, curiosities, books, titles, human friendships, or any earthly or heavenly thing, God, the supreme good, only excepted. That is a man's idol which prevents him from seeking and finding his All in God. Wiclif ends his epistle thus: My little sones, kepe ye you fro mawmitis, i.e. puppets, dolls, and such like; for thus Wiclif esteemed all images employed in religious worship. They are the dolls of a spurious Christianity, and the drivellings of religion in nonage and dotage. Protestants, keep yourselves from such mawmets! Amen - So be it! So let it be! And so it shall be, God being our helper, for ever and ever! Subscriptions in the Versions: - The end of the Epistle of the Apostle John. - Syriac. The First Epistle of John the apostle is ended. - Syr. Philoxenian. Nothing in either the Coptic or Vulgate. Continual and eternal praise be to God! - Arabic. The end. - Aethiopic; In this version the epistle is thus introduced: - In the name of the Father, and of the Son, and of the Holy Spirit, one God, the Epistle of John, the son of Zebedee, the evangelist and apostle of our Lord Jesus Christ; may his intercession be with us for ever and ever! Amen. In the Manuscripts: - The First of John. - AB. The First Epistle of John the evangelist. The First catholic Epistle of St. John the divine, written from Ephesus. The Epistle to the Parthians. - See several Latin MSS. The word amen is wanting in all the best MSS. and in most of the versions. For other matters relative to the epistle itself see the preface: and for its heavenly doctrine and unction read the text, in the original if you can; if not, in our own excellent translation.
Jamieson-Fausset-Brown Bible Commentary
Affectionate parting caution. from idols--Christians were then everywhere surrounded by idolaters, with whom it was impossible to avoid intercourse. Hence the need of being on their guard against any even indirect compromise or act of communion with idolatry. Some at Pergamos, in the region whence John wrote, fell into the snare of eating things sacrificed to idols. The moment we cease to abide "in Him that is true (by abiding) in Jesus Christ," we become part of "the world that lieth in the wicked one," given up to spiritual, if not in all places literal, idolatry (Eph 5:5; Col 3:5). Next: 2 John Introduction
John Gill Bible Commentary
Little children, keep yourselves from idols, Amen. From Heathen idols and idolatry, into which the saints in those times might be liable to be drawn, by reason of their dwelling among Heathen idolaters, and being related to them, and by the too great freedom used in eating things sacrificed to idols in their temples; and from all other idols that might be introduced by some who went by the name of Christians, as the Gnostics, who worshipped the images of Simon and Helena; and the passage may be an antidote against the worshipping of images, afterwards introduced by the Papists. Moreover, errors and false doctrines, which are the figments of men's minds, and what they are fond of, may be called idols, and should be guarded against, and abstained from; as also the lusts of men's hearts, and all the evil things that are in the world, which are adored by the men of it; and even every creature that is loved too much is an idol; hence covetousness is called idolatry; nor should any creature or thing be loved more than God or Christ: the one only living and true God, Father, Son, and Spirit, he is only to be worshipped, feared, and loved.
Tyndale Open Study Notes
5:21 In closing, John exhorts his flock to keep away from anything that might take God’s place in your hearts (literally keep yourselves from idols). In the context of 1 John, the primary idol would be any false teaching that takes people away from Jesus Christ, who is at once fully man and fully God.
1 John 5:21
The True God
20And we know that the Son of God has come and has given us understanding, so that we may know Him who is true; and we are in Him who is true—in His Son Jesus Christ. He is the true God and eternal life. 21Little children, keep yourselves from idols.
- Scripture
- Sermons
- Commentary
Separation From False Worship, Idolatry & Popish Principles
By John Calvin2.2K48:09EXO 20:3DEU 6:5PSA 16:4PSA 69:9MAT 6:331CO 10:141JN 5:21In this sermon on Psalm 16:4, John Calvin emphasizes the importance of dedicating ourselves to God once we have come to know Him as our Father and Jesus Christ as our Redeemer. He warns against idolatry and the worship of false gods, stating that those who give idols the honor due to God are estranged from Him. Calvin urges believers to reject superstitions, idolatries, and abuses that go against God's truth and obscure His honor. He encourages Christians to persevere in their faith and remain steadfast in the pure profession of their beliefs.
False Gods
By B.B. Caldwell2.0K45:32IdolatryEXO 20:1MRK 12:291JN 5:21In this sermon, the preacher emphasizes the importance of facing the consequences of our sins and the need to turn to a holy God. He highlights the Ten Commandments as the law that governs our relationship with both God and our fellow human beings. The preacher shares a personal experience where he disturbed a congregation by challenging them to examine their idols and put them on the altar. He emphasizes the commandment to love God with all our heart, mind, soul, and strength. The sermon concludes with the message of turning away from false gods and idols and waiting for the return of Jesus Christ.
A Call to Us
By Basilea Schlink1.6K04:35Radio ShowEXO 20:5MAT 6:24MAT 22:37MRK 8:34HEB 13:8JAS 4:71JN 5:21In this sermon, the speaker emphasizes the importance of giving God the first right to our time, money, possessions, and everything that makes life worth living. The speaker highlights that God is a holy, loving, and jealous God who yearns for our love and dedication. The sermon encourages listeners to turn away from their idols and turn to God alone. It emphasizes the need for zealous love for Jesus and a willingness to sacrifice for His honor, so that others may come to love Him. The sermon also emphasizes the power of faith in Jesus to break the chains of bondage and set us free from idolatry.
Soul Idolatry
By Dean Taylor1.5K1:24:30Idolatry1TI 2:152TI 2:21TIT 2:11HEB 11:11JN 2:151JN 5:21In this sermon, the preacher emphasizes the importance of summarizing key verses in the Bible to make them practical and applicable to our lives. He mentions several summary verses, such as 1 Timothy 2:15, which states that Jesus came to save sinners, and Hebrews 11:1, which defines faith as the substance of things hoped for. The preacher also highlights Titus 2:11 as a summary verse for grace, stating that the grace of God brings salvation to all. The main message of the sermon is to love not the world and its desires, but to live righteously and look forward to the glorious appearing of Jesus Christ.
Ministry From 1 John 5
By William MacDonald1.1K52:47MinistryPRO 25:2MAT 6:331JN 5:101JN 5:21In this sermon, the speaker reflects on a visit to a movie lot and compares the façade of the western village to the superficiality of the world. He emphasizes the importance of faith in seeing beyond the glitter and finding something real in the Lord Jesus Christ. The speaker then discusses the witness of men and how we trust in them, using the example of writing a check. He highlights the significance of receiving the witness of God, which is even greater. The sermon concludes by stating that this chapter of the Bible provides clear guidance on salvation and how to know if one is saved, emphasizing the simplicity of the gospel message. The speaker ends with a prayer for those who are still outside of Christ, urging them to come in repentance and acceptance of Jesus as Lord and Savior.
Unreached Peoples: The Drokpa People of the Himalayas
By Paul Hattaway1.0K00:00EXO 20:3PSA 96:5PSA 115:4ISA 44:9JER 10:2MAT 6:24ACT 17:291CO 10:141JN 5:21This sermon delves into the unique traditions and lifestyle of the Drogpa people, who live in a fruitful yet isolated area, practicing ancient customs and idol worship. Despite their abundance, they hold on to beliefs that hinder their spiritual growth, remaining unreached by the gospel. The sermon emphasizes the need for their hearts to turn from false gods to the true God, praying for a transformation from idolatry to worship of the one who brings unity and true fulfillment.
Divine Assurance
By H.J. Vine0JHN 6:53JHN 17:31JN 2:121JN 2:201JN 4:211JN 5:121JN 5:21H.J. Vine preaches about the divine assurance imparted by the Word of God to believers in Jesus Christ, emphasizing that even the youngest in faith can have the assurance of eternal life and forgiveness of sins through Christ's sacrifice. The sermon highlights the different stages of spiritual growth within the family of God - babes, young men, and fathers - and the vital possessions and prosperity enjoyed by true believers through the Unction received from Christ. It stresses the importance of abiding in the Son and the Father, knowing the truth, and keeping away from idols to prosper in divine love and eternal life.
Brazen Serpents
By Lewis Williams0NUM 21:81CO 10:141CO 12:41CO 13:1EPH 2:8COL 2:8HEB 12:2JAS 1:171JN 5:21Lewis Williams delivers a powerful sermon warning against burning incense to brazen serpents, emphasizing the danger of focusing more on God's gifts than on God Himself. He highlights how the children of Israel fell into idolatry by worshiping the brazen serpent instead of the Giver, a trap that many still fall into today by prioritizing church membership, baptism, communion, and spiritual gifts over a personal relationship with Christ. Williams urges believers to turn their eyes from the gifts to the Giver, emphasizing that salvation, healing, and spiritual growth come from Christ alone.
The Food Question
By T. Austin-Sparks0ACT 7:41ACT 14:15ACT 15:20ROM 2:221CO 8:41CO 10:192CO 6:161JN 5:21REV 9:20The preacher delves into the spiritual significance of idols, primarily derived from the Septuagint, where idols are considered products of fantasy and human hands, lacking any real power or significance. The Old Testament writers viewed idols as unreal gods, emphasizing their emptiness and inability to hear, see, or act. The New Testament usage of 'eidolon' is based on this understanding, warning against anything that takes priority over the True and Living God, including greed and materialistic desires. The sermon highlights the need to turn away from idols and worship the living God, as seen in various biblical passages.
1 John 5
By Daniel Steele01JN 5:11JN 5:21Daniel Steele preaches on the profound truths revealed in the First Epistle of John, emphasizing the essence of true faith as acknowledging Jesus as the Messiah, experiencing new birth, and being aflame with love for God and others. The inseparable connection between faith and love is highlighted, with a strong emphasis on obedience to God's commands as evidence of genuine love. The victory over the world through faith is discussed, along with the importance of having boldness in prayer and the continuous efficacy of the divine change in believers. The sermon concludes with a call to guard against idols and embrace the love and atonement of God through Jesus Christ for eternal life.
Dagon Was Fallen Upon His Face to the Earth
By F.B. Meyer0IdolatryDivine SupremacyEXO 12:121SA 5:3PSA 96:5ISA 2:18MAT 5:14JHN 1:5ROM 12:22CO 6:14COL 3:51JN 5:21F.B. Meyer emphasizes the confrontation between the Ark of the Lord and the idol Dagon, illustrating the supremacy of Jehovah over false gods. The fall of Dagon symbolizes the inevitable defeat of all idols when faced with the true power of God. Meyer encourages believers to invite the presence of God into their lives, assuring that the idols that have dominated them will fall away. This message serves as a reminder of God's ability to defend His greatness and the transformative power of allowing Christ to take full possession of one's heart. Ultimately, the sermon calls for a personal encounter with God that leads to the destruction of all that opposes Him.
Princess Diana’s Funeral as Global Event: A Prophetic Comment
By Art Katz0IdolatryProphetic VoiceEXO 20:3PSA 115:4ISA 42:8JER 10:14MAT 6:24ACT 19:271CO 10:14GAL 1:10COL 3:21JN 5:21Art Katz reflects on the global response to Princess Diana's funeral, questioning the depth of the adoration and the implications of such fervent devotion. He notes that while Diana was admired for her charitable work and beauty, her life and death may symbolize a troubling idolatry that distracts from true Christian faith. Katz emphasizes the need for the Church to critique this phenomenon rather than celebrate it, warning against the dangers of misplaced reverence for a figure who may not have acknowledged Christ. He draws parallels to biblical idolatry, urging a prophetic response to the cultural obsession with celebrity. Ultimately, he calls for a return to honoring God above all else.
God's Keeping
By Aaron Hills01SA 2:9PSA 91:11PSA 121:3JER 44:4MRK 13:331TH 5:232TI 3:31PE 1:41JN 5:21Aaron Hills preaches on the importance of God's keeping power and our responsibility to guard ourselves against backsliding. He emphasizes the need for constant trust, dependence on God, and faith in Jesus to maintain purity and holiness. Hills highlights the duty of watchfulness, comparing it to a lookout sailor on a ship, and stresses the role of conscience in detecting and avoiding sin. He also addresses the necessity of being dead to the world, rejecting worldly influences and embracing a life crucified to worldly desires.
Ezekiel 6:9
By Chuck Smith0God's LoveIdolatryDEU 6:5PSA 115:4EZK 6:9MAT 6:24ROM 12:21CO 10:14GAL 5:1JAS 4:41JN 4:191JN 5:21Chuck Smith emphasizes God's broken heart over the unfaithfulness of Israel, illustrating how God desires love in return for His own. He explains that while God created humanity for a loving relationship, many have chosen to pursue other 'gods' of pleasure, power, and lust, leading to alienation from Him. Despite Israel's rebellion, God continues to seek their restoration, highlighting the consequences of turning away from Him. Smith challenges listeners to reflect on their own lives and the distractions that may pull them away from a true relationship with God. Ultimately, he calls for a choice between serving God or succumbing to the false promises of other 'gods'.
Some Pithy Statements
By Art Katz0Idolatry vs. True FaithAuthentic WorshipISA 29:13MAT 6:1JHN 4:24ROM 12:11CO 1:272CO 5:7GAL 1:10EPH 2:8COL 1:271JN 5:21Art Katz emphasizes the dangers of idolatry and religion, which can provide emotional satisfaction without requiring true engagement with God. He critiques the superficiality of religious practices that lack genuine truth and worship, urging believers to seek a deeper, authentic relationship with God rather than mere adherence to doctrine. Katz highlights the importance of recognizing the magnitude of sin and suffering, and the need for a faith that is existential rather than merely credal. He calls for a shift from seeking human approval to embracing God's glory, which often lies in the unseen and lowly aspects of life.
Epistle 132
By George Fox0ISA 42:6EZK 37:26MRK 12:30JHN 1:4JHN 6:352CO 10:16EPH 4:15COL 2:2TIT 2:132PE 1:211JN 5:21REV 21:6George Fox preaches about the importance of walking in the truth and knowing one another in the measure of life, guided up to the Father of life, to be kept from idols and feigned love. He emphasizes waiting in the measure of life for hearts to be knit together, and the necessity of not willing anything with our own will but seeking God's will. Fox urges believers to mind their growth, perfecting, and steadfastness in the light of Christ for unity and nourishment, emphasizing the importance of waiting in the light that comes from Christ, the head.
Psalms 135:15
By Chuck Smith0IdolatryTrue WorshipEXO 20:3PSA 135:15ISA 44:9MAT 6:24JHN 4:24ROM 12:22CO 3:18GAL 5:171JN 3:21JN 5:21Chuck Smith emphasizes the danger of false concepts of worship, illustrating how people often create idols that reflect their own desires and intellect rather than worshiping the true God. He warns that these idols, whether material possessions or personal ambitions, are ultimately vain and lead to spiritual degradation. Smith highlights that a person becomes like their god, and if that god is false, so too will be the worshiper. He encourages believers to submit their lives to Jesus Christ, reminding them that true worship transforms and elevates them to become more like Him. The sermon serves as a call to examine what we truly worship and to ensure it aligns with the living God.
Babylon the Great Described
By Isaac Penington01JN 5:21Isaac Penington preaches about the deceptions and sins of Babylon the Great, describing how the city of confusion, where Antichrist reigns, leads people astray by imitating the ways of God without the life and power of the Spirit. He warns against idolatry, blasphemy, and sorceries that bewitch individuals into false worship and practices, emphasizing the need to worship God in spirit and truth.
The Unity of the Divine Being
By John Wesley0True ReligionUnity of GodEXO 34:6PSA 90:2ISA 44:8JER 23:24MAT 19:26MRK 12:32ROM 5:5GAL 5:22PHP 2:51JN 5:21John Wesley emphasizes the unity of God, asserting that there is only one God, one religion, and one true happiness for all humanity. He explains that God is eternal, omnipresent, all-perfect, and omnipotent, and that true religion consists of loving God and our neighbors. Wesley warns against the many idols that distract people from seeking happiness in God, including false religions and worldly desires. He concludes that genuine happiness and religion stem from a relationship with God, which leads to benevolence towards others. The sermon calls for a return to the foundational truth that we are made to find our happiness in God alone.
Spiritual Idolatry
By John Wesley0Seeking GodSpiritual IdolatryEXO 20:3PSA 115:4MAT 6:24ROM 12:2GAL 5:17COL 3:21TI 6:10HEB 12:1JAS 4:41JN 5:21John Wesley emphasizes the critical warning from 1 John 5:21 to keep ourselves from idols, explaining that true idolatry goes beyond physical statues to include anything that takes our heart away from God. He identifies various forms of idolatry, such as the desire of the flesh, the desire of the eyes, and the pride of life, urging believers to recognize that seeking happiness in these things leads to spiritual emptiness. Wesley encourages the congregation to seek true happiness in God alone, acknowledging our weaknesses and relying on His strength to overcome these idols. He calls for a deep conviction of the futility of worldly pursuits and a resolute commitment to pursue a relationship with God, which is the only source of true contentment and peace.
4. the Place Where This Epistle Was Written
By Daniel Steele0ACT 20:171TI 1:32TI 4:121JN 5:21REV 18:12Daniel Steele discusses the historical significance of John's residence in Ephesus, a major center of influence in the Orient during the early days of Christianity. The city was vital for trade and attracted significant Christian presence, including the Apostle Paul and other early Christian leaders. John likely resided in Ephesus before and after his exile on Patmos, drawing inspiration from the city's bustling markets for his vivid descriptions in Revelation. Despite the lack of direct evidence, subsequent writers like Justin Martyr and Irenaeus confirm John's connection to Ephesus, highlighting the strong Christian community that thrived there.
Star Wars ‘The Phantom Menace’: An Ultimate Idolatry?
By Art Katz0IdolatryConsumerismEXO 20:3MAT 6:24COL 3:51JN 5:21REV 18:3Art Katz addresses the pervasive influence of the Star Wars franchise and its associated marketing, expressing concern over the idolatry it represents in modern society. He critiques the obsession with consumerism and the detrimental effects it has on spirituality and community values, urging Christians to reflect on their engagement with such entertainment. Katz calls for a collective repentance and a rejection of the idolatrous culture that prioritizes profit over faith, warning that the current state of society may be a precursor to divine judgment. He emphasizes the need for parents to guide their children away from these distractions and to seek a deeper connection with God.
The Siege of Samaria
By Denis Lyle0DEU 28:53ISA 10:5ROM 4:21EPH 3:20PHP 4:191JN 5:21Denis Lyle preaches on the Siege of Samaria, highlighting the misery that sin brings, including idolatry in the land and the hypocrisy of the leader, King Jehoram. Despite the dire circumstances, Elisha proclaims God's mercy, promising an amazing, abundant, and available supply of food within 24 hours, showcasing the timing, terms, and tone of God's provision. However, there is mockery from a royal counsellor who doubts divine intervention, leading to divine retribution as God's Word is fulfilled. The sermon emphasizes the importance of faith, the consequences of unbelief, and the reminder that God is able to deliver in the darkest of circumstances.
1 John 5:21
By John Gill0IdolatryWorship of GodEXO 20:31JN 5:21John Gill emphasizes the importance of guarding against idolatry in his sermon on 1 John 5:21, urging believers to keep themselves from both physical idols and the spiritual idols that can arise from false doctrines and excessive love for worldly things. He warns that even good things can become idols if they are loved more than God, and he highlights the dangers posed by the surrounding culture and the influence of those who distort the truth. Gill calls for a commitment to worship the one true God, the Father, Son, and Holy Spirit, above all else.
Second River -- Idol Worship
By Martin Knapp0EXO 20:4PSA 115:4DAN 12:3ACT 17:291CO 10:14COL 3:51TH 1:91JN 5:21REV 21:8Martin Knapp delivers a powerful sermon on the sin of idolatry, emphasizing the First Commandment's prohibition of internal idolatry and the Second Commandment's prohibition of outward idolatry. He highlights God's severe view of idolatry, leading to death and eternal punishment in the lake of fire. Knapp warns against various forms of idolatry, such as worshiping images, dedicating temples to false gods, and rejecting Jesus for sham religion, stressing the importance of turning from idols to serve the living God.
- Adam Clarke
- Jamieson-Fausset-Brown
- John Gill
- Tyndale
Adam Clarke Bible Commentary
Little children - Τεκνια· Beloved children; he concludes with the same affectionate feeling with which he commenced. Keep yourselves from idols - Avoid the idolatry of the heathens; not only have no false gods, but have the true God. Have no idols in your houses, none in your churches, none in your hearts. Have no object of idolatrous worship; no pictures, relics, consecrated tapers, wafers, crosses, etc., by attending to which your minds may be divided, and prevented from worshipping the infinite Spirit in spirit and in truth. The apostle, says Dr. Macknight cautioned his disciples against going with the heathens into the temple of their idol gods, to eat of their feasts upon the sacrifices they had offered to these gods; and against being present at any act of worship which they paid them; because, by being present, they participated of that worship, as is plain from what St. Paul has written on the subject, Co1 8:10 (note). That is a man's idol or god from which he seeks his happiness; no matter whether it be Jupiter, Juno, Apollo, Minerva, Venus, or Diana; or pleasure, wealth, fame, a fine house, superb furniture, splendid equipage, medals, curiosities, books, titles, human friendships, or any earthly or heavenly thing, God, the supreme good, only excepted. That is a man's idol which prevents him from seeking and finding his All in God. Wiclif ends his epistle thus: My little sones, kepe ye you fro mawmitis, i.e. puppets, dolls, and such like; for thus Wiclif esteemed all images employed in religious worship. They are the dolls of a spurious Christianity, and the drivellings of religion in nonage and dotage. Protestants, keep yourselves from such mawmets! Amen - So be it! So let it be! And so it shall be, God being our helper, for ever and ever! Subscriptions in the Versions: - The end of the Epistle of the Apostle John. - Syriac. The First Epistle of John the apostle is ended. - Syr. Philoxenian. Nothing in either the Coptic or Vulgate. Continual and eternal praise be to God! - Arabic. The end. - Aethiopic; In this version the epistle is thus introduced: - In the name of the Father, and of the Son, and of the Holy Spirit, one God, the Epistle of John, the son of Zebedee, the evangelist and apostle of our Lord Jesus Christ; may his intercession be with us for ever and ever! Amen. In the Manuscripts: - The First of John. - AB. The First Epistle of John the evangelist. The First catholic Epistle of St. John the divine, written from Ephesus. The Epistle to the Parthians. - See several Latin MSS. The word amen is wanting in all the best MSS. and in most of the versions. For other matters relative to the epistle itself see the preface: and for its heavenly doctrine and unction read the text, in the original if you can; if not, in our own excellent translation.
Jamieson-Fausset-Brown Bible Commentary
Affectionate parting caution. from idols--Christians were then everywhere surrounded by idolaters, with whom it was impossible to avoid intercourse. Hence the need of being on their guard against any even indirect compromise or act of communion with idolatry. Some at Pergamos, in the region whence John wrote, fell into the snare of eating things sacrificed to idols. The moment we cease to abide "in Him that is true (by abiding) in Jesus Christ," we become part of "the world that lieth in the wicked one," given up to spiritual, if not in all places literal, idolatry (Eph 5:5; Col 3:5). Next: 2 John Introduction
John Gill Bible Commentary
Little children, keep yourselves from idols, Amen. From Heathen idols and idolatry, into which the saints in those times might be liable to be drawn, by reason of their dwelling among Heathen idolaters, and being related to them, and by the too great freedom used in eating things sacrificed to idols in their temples; and from all other idols that might be introduced by some who went by the name of Christians, as the Gnostics, who worshipped the images of Simon and Helena; and the passage may be an antidote against the worshipping of images, afterwards introduced by the Papists. Moreover, errors and false doctrines, which are the figments of men's minds, and what they are fond of, may be called idols, and should be guarded against, and abstained from; as also the lusts of men's hearts, and all the evil things that are in the world, which are adored by the men of it; and even every creature that is loved too much is an idol; hence covetousness is called idolatry; nor should any creature or thing be loved more than God or Christ: the one only living and true God, Father, Son, and Spirit, he is only to be worshipped, feared, and loved.
Tyndale Open Study Notes
5:21 In closing, John exhorts his flock to keep away from anything that might take God’s place in your hearts (literally keep yourselves from idols). In the context of 1 John, the primary idol would be any false teaching that takes people away from Jesus Christ, who is at once fully man and fully God.