We have two set examples before us as they both pray against their enemies. David who strongly prayed to God to avenge him and also to destroy all his enemies, However in the New Testament, When our Lord Jesus was betrayed, mocked and killed, He prayed that his enemies be forgiven instead of asking our Almighty to avenge him... In this way, Jesus taught us to be compassionate to those who surround us, be it a friend or an enemy...