After giving the second example, Paul again repeats his general rule (1 Corinthians 7:17, 1 Corinthians 7:20). This rule is directly applicable to believers who are married to unbelievers (1 Corinthians 7:12–16). They should remain in their situation, because it is the situation in (and to) which God has called them.
24 So, brothers, in whatever condition each was called, there let him remain with God.