The driving energy or fuel behind this kind of revenge is hatred or anger. It is a feeling of: “I really enjoyed it when ‘when what they had done to me came to them’ – I was so happy to see them suffer for what they had done, this is their punishment … tit for tat.” It is a type of joy that only increases our accounts of negative karmas with the other person, which as a result, increases our sorrow, instead of decreasing it, although it may give us an impression for a while that it is decreasing our sorrow. This kind of joy will only cause the radiation of a negative form of energy to the other person, which will not only give pain to the other person, but will also cause the radiation of the negative energy of hatred from the other person to us that will never bring us long term joy. Imagine someone meeting with an accident on the road and in a lot of pain and instead of helping that person immediately we smile at that person happy with what has happened to him or her. What energy will such a person send us in return? This example is on a physical level, but the same principle applies on a subtle level. So the next time something like this happens in our life, we need to remind ourselves only if we don’t have the slightest trace of joy inside us that we can safely say that we are free from any desire for revenge, even though it may be very subtle.