1 Thessalonians 4:1-3

Finally then, brothers and sisters, we request and urge you in the Lord Jesus, that as you received instruction from us as to how you ought to walk and please God (just as you actually do walk), that you excel even more.

For you know what instructions we gave you by the authority of the Lord Jesus.

For this is the will of God, your sanctification; that is, that you abstain from sexual immorality;