Genesis 38:26

And Judah acknowledged them, he could not help but recognize them, and said, She hath been more righteous than I, because that I gave her not to Shelah, my son. That was the result of his not having kept his word to Tamar: deceit, harlotry, incest. By managing to obtain children from Judah himself, Tamar had become guilty of a great sin, but her guilt was smaller than that of Judah. And he knew her again no more; it was a lesson for him to conquer the desires of his flesh and to struggle against sin in every form with greater earnestness.