Romans 3:4

God forbid: yea, let God be found true, but every man a liar; as it is written [Psalms 51:4], That thou mightest be justified in thy words, And mightest prevail when thou comest into judgment. [True, the Jew, by unbelief, had failed to improve his advantage in possessing the Scriptures; but that did not alter the fact that he had had the advantage. He had failed, but God had not failed. Had the unbelief of the Jew caused God to break his promises, then indeed might the advantage of the Jew have been questioned, for in that case it would have proven a vanishing quantity. But, on the contrary, God had kept faith, and so the advantage, though unimproved, had been an abiding quantity. And this accords with the holiness and sinlessness of God. He is ever blameless, and because he is so, he must ever be assumed to be so, even though such an assumption should involve the presumption that all men are false and untrue, as, indeed, they are in comparison with him: for David testified to the incomparable righteousness of God, that it was a righteousness which acquitted God of all unfaithfulness to his words, and which causes him to prevail whenever men call him to account or pass judgment upon him.]