1 Corinthians 7:15

On the other hand if the unbeliever in a mixed marriage wants to break up the marriage, the believing partner should allow him or her to do so. The reason for this is that God wants peace to exist in human relationships. It is better to have a peaceful relationship with an unbelieving spouse who has departed than it is to try to hold the marriage together. This is true if holding the marriage together will only result in constant antagonism and increasing hostility in the home. However, notice that the Christian does not have the option of departing (1 Corinthians 7:10-11).

Another view is that Paul meant that separation should be prevented if at all possible since that would disrupt the peace of the marriage union. [Note: Johnson, p. 1240.] However this view presupposes that peace existed between the husband and wife, which seems unlikely since one of them wanted a divorce from the other.

When the unbeliever departs, the Christian is no longer under bondage (Gr. douleuo, lit. to be a slave). Does this refer to bondage to hold the marriage together or bondage to remain unmarried? Many of the commentators believed it means that the Christian is free to let the unbeliever depart; he or she does not have an obligation to maintain the marriage. [Note: E.g., Robertson and Plummer, p. 143; Fee, The First . . ., pp. 302-3.] Among these some hold that the believer is not free to remarry (cf. 1 Corinthians 7:11). [Note: E.g., William A. Heth and Gordon J. Wenham, Jesus and Divorce.] Most of these believe that the Christian is free to remarry. [Note: E.g., Barrett, p. 166; Bruce, 1 and 2 Corinthians, p. 70; Lenski, pp. 294-95; Lowery, p. 518; Morris, p. 111; and Keener, p. 65.] The Greek text does not solve this problem. I think Paul was not addressing the idea of remarrying here.

I would counsel a Christian whose unsaved spouse has divorced him or her to remain unmarried as long as there is a possibility that the unsaved person may return. However if the unsaved spouse who has departed remarries, I believe the Christian would be free to remarry since, by remarrying, the unsaved partner has closed the door on reconciliation. [Note: See Robertson, 4:128.]