“Love your enemies, do good to those who hate you.” (Luke 6:27)
There are two main reasons why Christians should love their enemies and do good to them.
One is that it reveals something of the way God is. God is merciful.
“He makes his sun rise on the evil and on the good, and sends rain on the just and on the unjust” (Matthew 5:45).
“He does not deal with us according to our sins, nor repay us according to our iniquities” (Psalm 103:10).
“Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you” (Ephesians 4:32).
So when Christians live this way, we show something of what God is like.
The second reason is that the hearts of Christians are satisfied with God and are not driven by the craving for revenge or self-exaltation or money or earthly security.
God has become our all-satisfying treasure and so we don’t treat our adversaries out of our own sense of need and insecurity, but out of our own fullness with the satisfying glory of God.
Hebrews 10:34: “You joyfully accepted the plundering of your property [that is, without retaliation], since you knew that you yourselves had a better possession and an abiding one.” What takes away the compulsion of revenge is our deep confidence that this world is not our home, and that God is our utterly sure and all-satisfying reward.
So in both these reasons for loving our enemy we see the main thing: God is shown to be who he really is as a merciful God and as gloriously all-satisfying.
The ultimate reason for being merciful is to glorify God — to make him look great in the eyes of man.
Commentating Author unknown