John Chrysostom

"Having condemnation, because they have cast off their first faith." By faith he means, fidelity to their covenant. As if he had said, They have been false to Christ, they have dishonored Him, and transgressed His covenant.

Homily on 1 Timothy 15 ↗

Theophylact of Ohrid

By "faith" the apostle means a vow. They broke, he says, their covenant with Christ, and for that they are subject to condemnation.

Commentary on 1 Timothy ↗

Augustine of Hippo

The apostle mentions evil, unmarried women who are gossipers and busybodies and says that this vice springs from idleness. "And further," he says, "being idle, they learn to go about from house to house, and are not only idle, but gossipers as well as busybodies, mentioning things they ought not." He had previously said of these, "But refuse younger widows, for when they have wantonly turned away from Christ, they wish to marry and are to be condemned because they have broken their first pledge," that is, they did not persevere in …

On Holy Virginity 33.34-34.34 ↗

Jerome

The apostle, in concluding his discussion of marriage and virginity, is careful to observe a right balance in discriminating between them. Turning neither to the right hand nor to the left, he keeps to the King's highway and thus fulfills the injunction, "Be not righteous overmuch." … Do we not clearly show by this language what is typified in the Holy Scriptures by the terms right and left, and also what we take to be the meaning of the words "Be not righteous overmuch"? …

Letters 48.8 ↗

Thomas Aquinas

Then when he says, having damnation, he answers a tacit question. For someone might ask: wherein is the evil if they do marry? For you yourself say: a woman does not sin if she marry (1 Cor 7:36). Therefore, he says: having damnation, because they have made void their first faith, of chastity, which they vowed; for otherwise they would not have been accepted for support. …

Commentary on 1 Timothy ↗