Marriage is a covenant, a sacred bond between a man and a woman instituted by and publicly entered into before God. God's plan for the marriage covenant involves at least the following five vital principles:  (1) The permanence of marriage: Marriage is intended to be permanent, since it was established by God (Matthew 19:6; Mark 10:9). Marriage represents a serious commitment that should not be entered into lightly or unadvisedly. It involves a solemn promise or pledge, not merely to one's marriage partner, but before God. Divorce is not permitted except in a very limited number of biblical prescribed circumstances.  (2) The sacredness of marriage: Marriage is not merely a human agreement between two consenting individuals (a "civil union"); it is a relationship before and under God (Genesis 2:22).   (3) The intimacy of marriage: Marriage is the most intimate of all human relationships, uniting a man and a woman in a "one-flesh" union (Genesis 2:23 -25). Marriage involves "leaving" one's family of origin and "being united" to one's spouse, which signifies the establishment of a new family unit distinct from the two originating families. While "one flesh" suggests sexual intercourse and normally procreation, at its very heart the concept entails the establishment of a new kinship relationship between two previously unrelated individuals (and families) by the most intimate of human bonds.  (4) The mutuality of marriage: Marriage is a relationship of free self-giving of one human being to another (Ephesians 5:25-30). The marriage partners are to be first and foremost concerned about the well-being of the other person and to be committed to each other in steadfast love and devotion. This involves the need for forgiveness and restoration of the relationship in the case of sin. Mutuality, however, does not mean sameness in role. Scripture is clear that wives are to submit to their husbands and to serve as their "suitable helpers," while husbands are to bear the ultimate responsibility for the marriage before God (Ephesians 5:22-24; Colossians 3:18; Genesis 2:18, 20).  (5) The exclusiveness of marriage: Marriage is not only permanent, sacred, intimate, and mutual; it is also exclusive (Genesis 2:22-25; 1 Corinthians 7:2-5). This means that no other human relationship must interfere with the marriage commitment between husband and wife. For this reason, Jesus treated sexual immorality of a married person, including even a husband's lustful thoughts, with utmost seriousness (Matthew 5:28; 19:9). For the same reason, premarital sex is also illegitimate, since it violates the exclusive claims of one's future spouse. As the Song of Solomon makes clear, only in the secure context of an exclusive marital bond can free and complete giving of oneself in marriage take place.