Intimacy and Marriage
The church leaders in Corinth had written to Paul asking for advice about how to guide the believers in their relationships. Their past background of immoral behaviour required specific guidance if the church was to please the Lord. It may be that they had asked if God wanted everybody to be celibate, as Paul was? His answer was that it is not essential to be married; celibacy is good if it is a gift from God. However, marriage is the Lord's provision for most people to contain and enjoy the God-given desire for intimacy.
Both husband and wife have a responsibility to protect their spouse from immorality by encouraging intimacy within the marriage. Their bodies do not belong to themselves but to each other. That is not to say one person should demand or force himself or herself on the other, but that each should encourage the other to enjoy God's gift together. In that way husband and wife gladly serve each other.
But there are occasions for fasting from close contact, in the same way that we may fast from food. In the Old Testament, David's men were instructed not to have intimate relationships before a battle (1 Samuel 21:1-5). Paul said that special times of prayer for a couple may also demand that discipline; but only if they both agree and then come back together again, lest either of them be tempted into immorality.
This was practical wisdom from the apostle, and we do well to note it too. Marriage is not granted to everybody and the unmarried need to remain celibate like Paul. Satan will use periods of emotional separation in a marriage to weaken our discipline and tempt us into wrong relationships. Although many Christians have traditionally not talked about the intimate side of their marriage, these verses encourage us to do so. Rightly used, God's gift of physical intimacy is not dirty but beautiful, and is designed to unite people within their marriage so that their homes may be examples of the love of God in a loveless world.