In the beginning, God created one man and one woman. Not many men and many women, like all the other animals that filled the earth, but one of each. God did something special in his creation of mankind; he made them in his image. That means that there is a deep and profound meaning and purpose for marriage.
"'Therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh.' This mystery is profound, and I am saying that it refers to Christ and the church." Ephesians 5:31-32