The Principal of Sowing & Reaping

The worldly man may treat certain people kindly because he "likes" them: A Christian, trying to treat everyone kindly, finds himself liking more and more people as he goes on, including people he could not even have imagined himself liking at the beginning. This same spiritual law works terribly in the opposite direction. The Germans, perhaps, at first ill-treated the Jews because they hated them: afterwards they hated them that much more because they had a ill-treated them. The more cruel you are, the more you will hate; and the more you hate, the more cruel you will become, and so on, a vicious circle forever. Good and evil both increase at compound interest, that is why the little decisions you and I make every day or of such infinite importance. The smallest good act is the capture of a strategic point from which, a few months later, you may be able to go on to victories you never dreamed of. And apparently, trivial indulgence in lust or anger today is the loss of a ridge, or railway line or bridge head from which the enemy can launch an attack otherwise impossible. –CS Lewis

You become what you do. When you do something over and over, it becomes a habit and eventually part of your character. We are warned in Galatians 6:7, “Do not be deceived: God is not mocked, for whatever one sows, that will he also reap.” Love grows when it is planted. So does cruelty and hatred. The warning here is, ‘do not be deceived’ into thinking there are not generative consequences to our attitudes and actions. Practice love. Love, the Scripture says, never fails. Love begets love. Love grows.