Members of the Body

Christian must not give their members to sin:

Romans 6:13

And do not present your members as instruments of unrighteousness to sin, but present yourselves to God as being alive from the dead, and your members as instruments of righteousness to God.

They must give their members to God as instruments of righteousness:

Romans 6:13

And do not present your members as instruments of unrighteousness to sin, but present yourselves to God as being alive from the dead, and your members as instruments of righteousness to God.

19 I speak in human terms because of the weakness of your flesh. For just as you presented your members as slaves of uncleanness, and of lawlessness leading to more lawlessness, so now present your members as slaves of righteousness for holiness.

War in the members because of lusts:

James 4:1

Where do wars and fights come from among you? Do they not come from your desires for pleasure that war in your members?

Romans 7:23

But I see another law in my members, warring against the law of my mind, and bringing me into captivity to the law of sin which is in my members. 

The tongue is a small member but boasts great things:

James 3:5

Even so the tongue is a little member and boasts great things.

See how great a forest a little fire kindles! 

Fornication joins the members of the Christian to a harlot: 

 1 Corinthians 6:15 

Do you not know that your bodies are members of Christ? Shall I then take the members of Christ and make them members of a harlot? Certainly not!