marriage is a picture of the GOSPEL.

"In the home when a husband leads like Christ and a wife responds like the bride of Christ, there is a harmony and mutuality that is more beautiful and more satisfying than any pattern of marriage created by man. Biblical headship for the husband is the divine calling to take primary responsibility for Christlike, servant leadership, protection and provision in the home. Biblical submission for the wife is the divine calling to honor and affirm her husband’s leadership and help carry it through according to her gifts. This is the way of joy. For God loves his people and he loves his glory. And therefore when we follow his idea of marriage (sketched in texts like Gen 2:18-24; Prov 5:15-19; 31:10-31; Mark 10:2-12; Eph 5:21-33; Col 3:18-19; 1 Pet 3:1-7) we are most satisfied and he is most glorified.”

(Piper, John. "A Vision for Biblical Complementarity: Manhood and Womanhood Defined According to the Bible." Recovering Biblical Manhood and Womanhood: A Response to Evangelical Feminism. Edited by Piper, John and Wayne Grudem, eds. [Wheaton, IL: Crossway, 2006], 52-53).