1 Corinthians 7:39

A wife is bound [i.e., to stay married] for as long as her husband is alive. But if her husband dies, she is free to be married to anyone she wants; [but it must be] only in the Lord [i.e., he must be a faithful Christian].

2 Corinthians 6:14-17

Do not team up with unbelievers [i.e., in close relationships, such as marriage, etc.]. For what do righteousness and wickedness have in common? Or, what fellowship can light have with darkness?

Hebrews 6:16

For people make vows by someone greater [than themselves], and an argument is settled when someone takes an oath [that he is telling the truth].

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