[Yzupnick]

‎"Rejoice not when thine enemy falleth, and let not thy heart be glad when he stumbleth" (Proverbs, 24, 17)

[AngryParsley]

"The righteous shall rejoice when he seeth the vengeance: he shall wash his feet in the blood of the wicked." (Psalm 58:10)

[three14]

Which of course isn't actually contradictory. Provided that you can distinguish accurately between someone who is merely your "enemy" and someone who is objectively "wicked", you can decide whether or not to celebrate.

[hamai]

"Answer not a fool according to his folly, lest you be like him yourself. Answer a fool according to his folly, lest he be wise in his own eyes." (Proverbs 26:4-5)