Ignatius of Antioch warns against various false teachings and beliefs that distort the truth of God and Christ, labeling those who deny Christ as liars and followers of the devil. He emphasizes the importance of confessing the true nature of Christ as the Son of God and the Word made flesh, while rejecting teachings that lead to corruption and denial of the faith. Ignatius urges believers to remain united in heart and mind, steadfast in their love for God and Christ, and to avoid falling into the traps set by the deceitful spirits of the world.

If any one preaches the one God of the law and the prophets, but denies Christ to be the Son of God, he is a liar, even as also is his father the devil, and is a Jew falsely so called, being possessed of mere carnal circumcision. If any one confesses Christ Jesus the Lord, but denies the God of the law and of the prophets, saying that the Father of Christ is not the Maker of heaven and earth, he has not continued in the truth any more than his father the devil, and is a disciple of Simon Magus, not of the Holy Spirit. If any one says there is one God, and also confesses Christ Jesus, but thinks the Lord to be a mere man, and not the only-begotten God, and Wisdom, and the Word of God, and deems Him to consist merely of a soul and body, such an one is a serpent, that preaches deceit and error for the destruction of men. And such a man is poor in understanding, even as by name he is an Ebionite. If any one confesses the truths mentioned, but calls lawful wedlock, and the procreation of children, destruction and pollution, or deems certain kinds of food abominable, such an one has the apostate dragon dwelling within him. If any one confesses the Father, and the Son, and the Holy Ghost, and praises the creation, but calls the incarnation merely an appearance, and is ashamed of the passion, such an one has denied the faith, not less than the Jews who killed Christ. If any one confesses these things, and that God the Word did dwell in a human body, being within it as the Word, even as the soul also is in the body, because it was God that inhabited it, and not a human soul, but affirms that unlawful unions are a good thing, and places the highest happiness in pleasure, as does the man who is falsely called a Nicolaitan, this person can neither be a lover of God, nor a lover of Christ, but is a corrupter of his own flesh, and therefore void of the Holy Spirit, and a stranger to Christ. All such persons are but monuments and sepulchres of the dead, upon which are written only the names of dead men. Flee, therefore, the wicked devices and snares of the spirit which now worketh in the children of this world, lest at any time being overcome, ye grow weak in your love. But be ye all joined together with an undivided heart and a willing mind, "being of one accord and of one judgment," being always of the same opinion about the same things, both when you are at ease and in danger, both in sorrow and in joy. I thank God, through Jesus Christ, that I have a good conscience in respect to you, and that no one has it in his power to boast, either privately or publicly, that I have burdened any one either in much or in little. And I wish for all among whom I have spoken, that they may not possess that for a testimony against them.