Verses with the word adversary in the New Testament (5 verses):

Matthew 5:25
Agree with thine adversary quickly, whiles thou art in the way with him; lest at any time the adversary deliver thee to the judge, and the judge deliver thee to the officer, and thou be cast into prison.

Luke 12:58
When thou goest with thine adversary to the magistrate, as thou art in the way, give diligence that thou mayest be delivered from him; lest he hale thee to the judge, and the judge deliver thee to the officer, and the officer cast thee into prison.

Luke 18:3
And there was a widow in that city; and she came unto him, saying, Avenge me of mine adversary.

1 Timothy 5:14
I will therefore that the younger women marry, bear children, guide the house, give none occasion to the adversary to speak reproachfully.

1 Peter 5:8
Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour: