Matt. 19:5, Gen. 2:24, 1 Cor. 6:16
The act of sex seals the covenant whereby the two become one flesh.
Husbands and wives communicate on three levels: body, soul, and spirit (1 Thess. 5:23). Sex is communication on the physical level.
Prov. 5:18-19, 1 Cor. 7:2,3,5,9, Heb. 13:4
God created sex within marriage for husbands and wives to enjoy each other and bond.
Gen. 1:28--"Be fruitful and multiply"