John Chrysostom

Ver. 14. "Not giving heed," he says, "to Jewish fables." The Jewish tenets were fables in two ways, because they were imitations, and because the thing was past its season, for such things become fables at last. For when a thing ought not to be done, and being done, is injurious, it is a fable even as it is useless. As then those ought not to be regarded, so neither ought these. For this is not being sound. For if thou believest the Faith, why dost thou add other things, as if the faith were not sufficient to justify? …

Homily on Titus 3 ↗

Theophylact of Ohrid

So then, soundness consists in not introducing anything false, anything foreign to the faith; just as submitting oneself to the law does not mean boldly relying on faith that it is sufficient for salvation. This is no small error. Jewish customs are doubly fables: both because they are untimely and utterly useless, and because attending to them is harmful. So then, just as one must not believe fables, neither should one believe these. Of course, the holy books of the Old Testament, rightly understood, are not fables. …

Commentary on Titus ↗

Theodoret of Cyrus

Paul uses the term "Jewish fables" not to describe the law but the interpretation of the law put forward by the Jews. The Lord accuses them of this very thing when he says, "Why do you transgress the law for the sake of your own traditions?"

Interpretation of the Letter to Titus

Jerome

Those who have this health of faith and doctrine and sound words, do not heed Jewish fables and the commands of men who turn away from the truth. Let us acquiesce for a short time to the Jews, and listen patiently to their foolishness, and then we will understand what the Jewish tales are which have no authority from Scripture, nor any rational basis, but are the product of the fables and imaginations of certain people about animals and legends, of whom Isaiah prophesied, saying: "This people honors me with their lips, but their …

Commentary on Titus ↗

Thomas Aquinas

The road to this soundness is to avoid the errors of the Jews; hence he says, not giving heed to Jewish fables. For in the law there are two types of articles: those dealing with beliefs, and those dealing with precepts of religion, which were to be observed in divine worship. The first he calls fables, and the second commandments of men and not of God. In this he seems to be condemning the old law as the Manicheans do. …

Commentary on Titus ↗