1 Corinthians 7:39

A wife is bound to her husband as long as he lives; but, if the husband should pass to his rest, the widow is free to marry any one she wishes, provided he is a believer.

2 Corinthians 6:14-17

Do not enter into inconsistent relations with those who reject the Faith. For what partnership can there be between righteousness and lawlessness? or what has light to do with darkness?

Hebrews 6:16

Men, of course, swear by what is greater than themselves, and with them an oath is accepted as putting a matter beyond all dispute.

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