The Bible says that “marriage should be honored by all, and the marriage bed kept pure, for God will judge the adulterer and all the sexually immoral” (Hebrews 13:4). Scripture never says what a husband and wife are or are not allowed to do sexually, so how can we know if something is sexually permissible between a husband and wife? The Bible gives us general principles regarding sex within marriage:
If the sexual act in question satisfies these principles, and both the husband and wife are agreeable to loving each other in that way, there is no biblical case for declaring it to be a sin. The principle of “mutual consent” applies to abstaining from sex (1 Corinthians 7:5) and to whatever is done sexually within a marriage. Neither spouse should be coerced into doing something he or she is not completely comfortable with or thinks is wrong. If a husband and wife both agree that they want to try something (e.g., oral sex, different positions, sex toys, etc.), then the Bible does not give any reason why they cannot.
There are a few things, though, that are never allowable for a married couple. The practice of “swapping,” “swinging,” or “bringing in an extra” (threesomes, foursomes, etc.) is adultery (Galatians 5:19; Ephesians 5:3; Colossians 3:5; 1 Thessalonians 4:3). Adultery is sin even if one’s spouse allows, approves, or even participates in it. Viewing pornography is another practice that should be off-limits for a married couple. Porn appeals to the “lust of the flesh and the lust of the eyes” (1 John 2:16) and is therefore condemned by God.
Scripture provides great freedom in the bedroom for a husband and wife. As long as a married couple’s sexual practices are God-honoring, exclusive, loving, other-oriented, unifying, and mutually agreed upon, they carry God’s blessing.