This is the will of God, your holiness: that you refrain from immorality, that each of you know how to acquire a wife for himself in holiness and honor, not in lustful passion as do the Gentiles who do not know God; nor to take advantage of or exploit a brother in this matter, for the Lord is an avenger in all these things, as we told you before and solemnly affirmed.  For God did not call us to impurity but to holiness.  Therefore, whoever disregards this, disregards not a human being but God, who gives his holy Spirit to you.

I Thessalonians 4:3-8