It's not our place, Vengeance belongs to God.
Recently, during a friendly conversation with a Christian friend of mine, we got into the story of my grand mother who had alot of experience on life situations.
When I was young, my grand mother once told me a story of how someone wanted to hurt her spiritually and requested for salt. She then offered the person more and more than the one spoon of salt requested. Some days later, the person passing by saw her and kept a very squeezing face then after she excused him/her (can't remember the gender, was very long when she told me that story] and exchanged pleasantries, she was asked what she put in the salt she offered.
The bottom line is that, the excess salt actually fought the evil the person intended doing with a spoon of salt.
My pastor once told me that the best way to conquer evil is by rendering so much love. So much love that the evil will be stained with love and less perceived as evil. It's like adding alot of salt to a bitter substance. The bitter substance develops a conflicting taste.
As Christians, we are instructed that when our neighbors slap us on one side of the cheek, we should render the other side.
This is not an attempt to befool us but an attempt to say that Vengeance is not suppose to be in our hands.
The moment you take vengeance you give the third party a picture of doubt.
Let's say for instance Mr A slapped Mr B, as Mr B slapped Mr A back, Mr C came in to see him slapping Mr A who happened to be his Father. Mr C slapped Mr B without any questioning and Mr B returned the slap To Mr C, just then Mr D walked in and saw Mr C being slapped who happened to be his Father, Mr D then slapped Mr B...
This is what Vengeance does to us. The other parties may not really know your side of the story and finally you get to lose what benefit or help they would have rendered. What if as Mr A slapped you, C, D all came in and saw him slapping you? In the course of taking vengeance, Mr B received 2 slaps that were uncalled for.
But when God handles vengeance, as the master planner He knows how to programme the whole episode and turn everything around for our good.
In the course of disobeying him by taking vengeance, you have altered the plans he had for you.
When you give excess love to your enemy, that love is a powerful weapon that fights for you.
1st Peter 4:8 : Above all, love each other deeply, because love covers over a multitude of sins.
Luke 6:27 : But to you who are listening I say:love your enemies, do good to those who hate you.
1st Corinthians 13:4-13 : 1 Corinthians 13:4 Charity suffereth long, and is kind; charity envieth not; charity vaunteth not itself, is not puffed up, 13:5 Doth not behave itself unseemly, seeketh not her own, is not easily provoked, thinketh no evil; 13:6 Rejoiceth not in iniquity, but rejoiceth in the truth; 13:7 Beareth all things, believeth all things, hopeth all things, endureth all things. 13:8 Charity never faileth: but whether there be prophecies, they shall fail; whether there be tongues, they shall cease; whether there be knowledge, it shall vanish away. 13:9 For we know in part, and we prophesy in part. 13:10 But when that which is perfect is come, then that which is in part shall be done away. 13:11 When I was a child, I spake as a child, I understood as a child, I thought as a child: but when I became a man, I put away childish things. 13:12 For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known. 13:13 And now abideth faith, hope, charity, these three; but the greatest of these is charity. (In this context, charity is love)
It is our place to love, love and love. Whatever the Evil plots against us, God is watching and in due time, we shall all reap our good while the evil reap their evil. By the time we interfere by taking vengeance, we might end up losing our reward.