God created human beings as male and female (Gen. 1:27). The complementary, relational nature of the human race as “male and female” reflects the created order given by God when He created human beings “in His image” (Gen. 1:26-27; 5:1, 3; 9:6; 1 Cor. 11:7; Jms. 3:9; cf. Rom. 8:29; 2 Cor. 3:18; Eph. 4:23-24; Col. 3:10).
Scripture grants two life-enhancing options for sexual behavior: monogamous marital relations between one man and one woman (Gen. 1:27-28; 2:18, 21-24; Matt. 19:4-6; Mk. 10:5-8; cf. Heb. 13:4) or sexual celibacy (1 Cor. 7:7; Matt. 19:12).
In Scripture monogamous heterosexual marriage bears a significance which goes beyond the regulation of sexual behavior, the bearing and raising of children, the formation of families, and the recognition of certain economic and legal rights. Marriage between a woman and a man is emphatically declared in Scripture to create a “one flesh” union (Gen. 2:23-24; Matt. 19:5), which in turn signifies the mystery of the union between Christ and His body, the Church (Eph. 5:22- 33). This means that the foundational understanding of marriage is as a covenant grounded in promises between a man and a woman which finds its divinely intended expression in the “one flesh” union of husband and wife, and between the “one flesh” union of husband and wife and God (cf. Prov. 2:16-17; Mal. 2:14; Eph. 5:31-32).