The two shall become one flesh

Ephesians 5:25-33
"Husbands, love your wives, just as Christ also loved the church 
and gave Himself up for her, so that He might sanctify her, 
having cleansed her by the washing of water with the word, 
that He might present to Himself the church in all her glory, 
having no spot or wrinkle or any such thing; 
but that she would be holy and blameless. 

So husbands ought also to love their own wives as their own bodies. 
He who loves his own wife loves himself; 
for no one ever hated his own flesh, but nourishes and cherishes it, 
just as Christ also does the church, because we are members of His body. 

For this reason a man shall leave 
his father and mother 
and shall be joined to his wife, 
and the two shall become one flesh. 

This mystery is great; but I am speaking with reference to Christ 
and the church. Nevertheless, each individual among you also 
is to love his own wife even as himself, and the wife must see to it 
that she respects her husband."