2 Thessalonians 1:6
since God considers it only just to repay with suffering those who are making you suffer
Matthew 7:2
For you will be judged by the standard you judge by, and men will pay you back with the same measure you have used with them.
James 2:13
For the merciless will be mercilessly judged; but mercy will triumph over judgment.
Revelation 13:10
Whoever is destined for captivity will go into captivity; whoever kills with the sword must be killed with the sword. On this fact rests the endurance and fidelity of God's people.
Revelation 16:6
for they shed the blood of your people and prophets, and you have given them blood to drink, as they deserve."
Revelation 19:2
for his judgments are sound and upright. For he has passed judgment upon the great idolatress who corrupted the earth with her idolatry, and he has avenged the blood of his slaves upon her!"