Bible verses about "fidelity" | UKJV

¹⁸ Whosoever puts away his wife, and marries another, commits adultery: and whosoever marries her that is put away from her husband commits adultery.

⁴ Love (o. agape) suffers long, and is kind; love (o. agape) envies not; love (o. agape) vaunts not itself, is not puffed up, ⁵ Does not behave itself unseemly, seeks not her own, is not easily provoked, thinks no evil; ⁶ Rejoices not in iniquity, but rejoices in the truth; ⁷ Bears all things, believes all things, hopes all things, endures all things.

⁴ Marriage is honourable in all, and the bed undefiled: but whoremongers and adulterers God will judge.