" We don’t stop there, though. Jesus came to save sinners, not the righteous, and he calls all of us to repentance. What does repentance look like in these situations? Take the worst-case scenario of the unbiblical divorced and remarried couple. They have, in fact, committed an adulterous act in the remarriage (Matt. 5:31–32). What now would we have them to do? Do they repent of this adultery by divorcing again? How can they repent of sin by repeating it, abandoning yet another spouse, breaking yet another set of vows? No. The Scripture does in many of these cases see the act of severing a marriage, and entering another, as an adulterous act. This does not mean that, once entered into, they are not marriages. The Samaritan woman at the well had five “husbands”—and Jesus uses that word. "
― Russell D. Moore , The Storm-Tossed Family: How the Cross Reshapes the Home