For me, hate, and unforgiveness towards another are poison to my spirit. I've been tempted and succumbed to temptation to these attitudes more times than I care to remember. However, I've come to the conclusion that when these attitudes come into my life, that the the best thing for me to do is to get rid of them. I hasten to add that the task of ridding myself of these - I can only call them sins, but I speak only for myself - is not easy. Harboring and nourishing hatred or unforgiveness against any other person is toxic to me.
The realization of just how toxic such attitudes can be came to me when George Bush went to war in Iraq on the basis of lies, which I knew to be lies. I became nearly obsessed with him and Dick Cheney, in what I finally, after a long period of time, came to see was quite an unhealthy condition for me. You see, my turning away from hate was partly a selfish act for the sake of my own soul and spirit
For me, the first step away is an act of will to have hate or unforgiveness toward anyone out of my life. However, willing the attitude to be gone does not magically banish it away, and there's no point in saying it's gone, when it is not. Denial only worsens the situation. The process takes time and the help of God's grace. I find that the method that works best for me is to pray for the person I hate or against whom I harbor unforgiveness and ask God to help me be rid of the attitude. In the beginning, I had to force myself to pray for Bush and Cheney, and I nearly choked on the prayers, but as time passed, I became less obsessed and compulsive about them - not that I liked their policies any better - but I had my life back out of the grip of my hatred for them. I don't think I have hated anyone since, and I hope that I never do.
With my father, who was an alcoholic and who was mean even when he wasn't drinking and made our family life miserable when my sisters and I were growing up, I went through a similar process. Long after I was grown, married and living away from him, I came to the realization that I must forgive him. The words of The Lord's Prayer haunted me. In the prayer, I ask God to forgive me as I forgive others. I knew that I had to forgive him, but I didn't really want to, and, in truth, I didn't think it was possible. I told God, "All right, I want to forgive my father, but there's no way I can do it on my own. If you want me to forgive him, then you will have to help me." For quite a long time, maybe a year, I couldn't do it, but I prayed for him and that forgiveness would come, and finally, I was able to say with honesty that I forgave him. He died a couple of years later, and I'm thankful to this day that forgiveness came before his death.
Dealing with hate and unforgiveness is the work of a lifetime for me. Temptation is everywhere. Nevertheless, I believe that Jesus is wise when he tells me to love my enemies and teaches me to pray to forgive as I want to be forgiven. Out of obedience to the words of Jesus and for my own sake, to free myself from their toxicity, I believe it is right for me to let go of hate and unforgiveness as God gives me the grace to do so.