From this we now see: 1. How, at that time, church discipline among the people of God had come into disuse, and the divine ordinance had been almost completely forgotten.
The Lord God had given an earnest command in Deuteronomy 23:17, “No harlot should be found among the daughters of Israel.” But we hear in this text about a woman who was a well-known sinner. In John 8:3, they bring a woman to the Lord Christ who was caught in open adultery, and their first question was what they should do with her, as if God’s commandment had been entirely buried.
This all came from the deception and seduction of the devil. He had not only seduced God’s people at that time into idolatry, which is spiritual adultery, but had also popularized among them the sins of harlotry and adultery, even as spiritual and physical harlotry are often found together, the defilement of the soul through false teaching and the defilement of the body through unchastity, zeal for idolatry, and the evil burning for harlotry.
Even as it was before the first coming of Christ that, among many other sins, harlotry and adultery were particularly in vogue, so it also goes now before the second coming of Christ, where the horrible, awful sins against the Sixth Commandment threaten to come crashing in like a flood, spurred on by the fact that such sins are not punished with just and proper zeal by the government. Just as the Sodomites were burning with lust when their downfall was right at the door, so that they had to be burned up with fire and brimstone from heaven (Gen. 18), so also will similar sodomite sins be running rampant when heaven and earth are about to be burned up with fire (2 Pet. 3:10).
(Sermon for Mary Magdalene-July 22, Postilla Volume 3 by Johann Gerhard, Repristination Press, page 108-109)