Liar (5583) (pseustes from pseudomai = to lie) is one who speaks falsehood, untruth, and so attempts to deceive. Thayer adds that pseustes describes "one who breaks faith, a false or faithless man." There are 10 uses of pseustes in the NT - John 8:44 "You are of your father the devil, and you want to do the desires of your father. He was a murderer from the beginning, and does not stand in the truth, because there is no truth in him. Whenever he speaks a lie, he speaks from his own nature; for he is a liar, and the father of lies. John 8:55 and you have not come to know Him, but I know Him; and if I say that I do not know Him, I shall be a liar like you, but I do know Him, and keep His word. Romans 3:4 May it never be! Rather, let God be found true, though every man be found a liar, as it is written, "That Thou mightest be justified in Thy words, And mightest prevail when Thou art judged." 1 Timothy 1:10 and immoral men and homosexuals and kidnappers and liars and perjurers, and whatever else is contrary to sound teaching, Titus 1:12 (note) One of themselves, a prophet of their own, said, "Cretans are always liars, evil beasts, lazy gluttons." 1 John 1:10 If we say that we have not sinned, we make Him a liar, and His word is not in us. 1 John 2:4 The one who says, "I have come to know Him," and does not keep His commandments, is a liar, and the truth is not in him; 1 John 2:22 Who is the liar but the one who denies that Jesus is the Christ? This is the antichrist, the one who denies the Father and the Son. 1 John 4:20 If someone says, "I love God," and hates his brother, he is a liar; for the one who does not love his brother whom he has seen, cannot love God whom he has not seen. 1 John 5:10 The one who believes in the Son of God has the witness in himself; the one who does not believe God has made Him a liar, because he has not believed in the witness that God has borne concerning His Son. There are 2 uses of pseustes in the Septuagint - Psalm 116:11 I said in my alarm, "All men are liars." Proverbs 19:22 What is desirable in a man is his kindness, and it is better to be a poor man than a liar. NIDNTT adds that... In the NT 15 different words contain the root pseud- (false). These are found in nearly all the NT writings, but whereas the Synoptic Gospels make only very sparing use of them, they play an important role in Johannine and Pauline writings. Besides the simple use of vb., noun and adj. (pseudomai, lie; pseudos, lie; pseustes, liar; pseudes, deceitful), which comprise the major part of the NT instances, there are numerous compound words. These include: pseudadelphos, false brother (2 Cor. 11:26; Gal. 2:4; Brother); pseudapostolos, false apostle (2 Cor. 11:13; Apostle); pseudodidaskalos, false teacher (2 Pet. 2:1; Teach); pseudologos, speaking lies (1 Tim. 4:2); pseudomartyria, false witness (Matt. 15:19; 26:59); pseudomartys, one who gives false witness (Matt. 26:60; 1 Cor. 15:15; Witness); pseudoprophetes, false prophet (Matt. 7:15; 24:11, 24; Mk. 13:22; Lk. 6:26; Acts 13:6; 2 Pet. 2:1; 1 Jn. 4:1; Rev. 16:13; 19:20; 20:10; Prophet); and pseudochristos, false Christ (Matt. 24:24; Mk. 13:22). (Brown, Colin, Editor. New International Dictionary of NT Theology. 1986. Zondervan) If all mankind were to agree that God had been unfaithful to His promises, it would only prove that all are liars and God is true. For example in Titus we read... Titus 1:1 (see notes) Paul, a bond-servant of God, and an apostle of Jesus Christ, for the faith of those chosen of God and the knowledge of the truth which is according to godliness 2 (see note) in the hope of eternal life, which God, who cannot lie, promised long ages ago (cp Nu 23:19, 1Sa 15:29, Heb 6:18) If every human being who ever lived declared that God is faithless, God would still be found true and every man who testified against Him would be proven to be found a liar. AS IT IS WRITTEN: kathos gegraptai (3SRPI): (Job 36:3; Ps 51:4; Mt 11:19) Now Paul turns to the OT to support his statement that God can never be considered to be false or unfaithful, even when He judges not only Gentiles but also Jews. Paul quotes Psalm 51:4 from the Septuagint or LXX not the Hebrew. In this text David pictures himself in a heavenly tribunal before the divine Judge. There he makes his confession of guilt and acknowledges that God is proved right in what He says and just in His judgment against David. Ps 51:4 (Hebrew) Against Thee, Thee only, I have sinned, And done what is evil in Thy sight, So that Thou art justified when Thou dost speak, And blameless when Thou dost judge. Spurgeon comments on Ps 51:4: Against thee, thee only have I sinned. The virus of sin lies in its opposition to God: the psalmist's sense of sin towards others rather tended to increase the force of this feeling of sin against God. All his wrong doing centered, culminated, and came to a climax, at the foot of the divine throne. To injure our fellow men is sin, mainly because in so doing we violate the law of God. The penitent's heart was so filled with a sense of the wrong done to the Lord Himself, that all other confession was swallowed up in a broken hearted acknowledgment of offence against Him. And done this evil in thy sight. To commit treason in the very court of the King and before His eye is impudence indeed: David felt that his sin was committed in all its filthiness while Jehovah Himself looked on. None but a child of God cares for the eye of God, but where there is grace in the soul it reflects a fearful guilt upon every evil act, when we remember that the God Whom we offend was present when the trespass was committed. That Thou mightest be justified when thou speakest, and be clear when thou judgest. He could not present any argument against divine justice, if it proceeded at once to condemn him and punish him for his crime. His own confession, and the judge's own witness of the whole transaction, places the transgression beyond all question or debate; the iniquity was indisputably committed, and was unquestionably a foul wrong, and therefore the course of justice was clear and beyond all controversy. Sir Richard Baxter comments on That thou mightest be justified when thou speakest, and be clear when thou judgest: But hath not David a defence for it here, and that a very just one? For, in saying, "Against thee, thee only, have I sinned, that thou mightest be justified in thy saying," doth he not speak as though he had sinned to do God a pleasure? therefore sinned that God might be justified? And what can be more said for justifying of God? But far is it from David to have any such meaning; his words import not a lessening but an aggravating of his sin, as spoken rather thus: Because a judge may justly be taxed of injustice if he lay a greater punishment upon an offender than the offence deserves; therefore to clear thee, O God, from all possibility of erring in this kind, I acknowledge my sins to be so heinous, my offences so grievous, that thou canst never be unmerciful in punishing though thy punishment should be never so unmerciful. For how can a judge pass the bounds of equity where the delinquent hath passed all bounds of iniquity? and what error can there be in thy being severe when the greatness of my fault is a justification of severity? That thou canst not lay so heavy a doom upon me, which I have not deserved? Thou canst not pronounce so hard a sentence against me, which I am not worthy of. If thou judge me to torture, it is but mildness; if to die the death, it is but my due; if to die everlastingly, I cannot say it were unjust. Sir Richard Baker.