Paul said that there is no need to separate if the other party does not care. How do you know that the Lord will not save him through you? If he does not care and wants to continue living with you, Paul said that you should be at peace with him and should not leave. He said that an unbeliever can be sanctified through a believer. He said also, “For how do you know, O wife, whether you will save your husband? Or how do you know, O husband, whether you will save your wife?” (v. 16). If the other party wants to leave, that is his concern, not yours. But if he does not want to leave, you have to believe that the Lord will save him. Paul said that it would be easy for him to be saved. It may not be that easy for the Lord to save others, but it would surely be easy for the Lord to save one who is already yours. We need to deal with this matter by taking such a stand.
Some brothers and sisters have another problem: They are engaged to unbelievers. What should they do?
It is clear that the Lord does not want us to marry unbelievers. If someone is already engaged to an unbeliever, the best thing would be for the unbelieving fiancé or fiancée to voluntarily break the engagement. The two are not yet married; they only have an agreement to marry. If the Lord opens the way for the unbelieving side to voluntarily break the agreement because the other one has believed in the Lord, that is the best solution.
However, it is often impossible to have such a solution. Because a marriage agreement exists, the other party may not easily let go just because you have believed in the Lord. At such times, you need to realize that an engagement to a person is a covenant with that person. Such a covenant is a promise you have made before God. A Christian cannot arbitrarily annul a covenant just because he has believed in the Lord. Any covenant is holy in the eyes of God. You can suggest a dissolution to the other party. The other party can initiate such a dissolution, or you can initiate it. The proposal need not be initiated by the other party. This is different from the earlier case. In the case of a marriage, the other party must initiate it. In the case of an engagement, you can initiate the dissolution of the engagement. If the other party insists that you fulfill the marriage agreement, you have to fulfill it. Once something comes out of the mouth of a Christian, he has to honor it; he cannot annul it arbitrarily. We receive salvation because God honors His word. If God did not honor His word, there would not be any salvation at all. Therefore, you have to negotiate with the other party. If the other party is unwilling to dissolve the relationship, you have to marry him or her.
Psalm 15:4 says, “Should he swear to his harm, / He does not change.” After the Israelites entered the land of Canaan, the Gibeonites deceived them with dry, moldy bread, old patched shoes, and worn garments. They said that they came from a far country, and Joshua promised not to kill them. Later, he found out that they were actually from a near country. Because a covenant had been made with them, God would not allow the Israelites to kill them. At the most, they were made woodcutters and drawers of water (Josh. 9:3-27). Honoring one’s covenant is a serious matter in the Bible. It is all right for you to annul an engagement only if the other party is willing to annul it. But if the other party is not willing to annul it, you cannot annul it. The covenant with the Gibeonites produced serious consequences. Rain was withheld from heaven because Saul slaughtered the Gibeonites. David was forced to ask the Gibeonites what he should do for them. The Gibeonites demanded that seven of the sons of Saul be hung, and David had to comply (2 Sam. 21:1-6). God will not allow us to breach a covenant arbitrarily. We must learn to honor any covenant we make. We cannot do anything that is unrighteous.