The Great I AM teaches that when you send out a thought, it is a sword. In the Tarot Swords are the mind. The Tarot considers Swords to be negative energy, but actually Swords are Divine Mind sending us information. When we don't like, or don't want to accept, the information Divine Mind sends, we put the connotation "negative" on it, but in reality, a thought is a sword as it cuts through the surface of understanding.
Furthermore, every thought that we wrap with a feeling is believed to stay in eternity until it manifests and creates itself as a reality. The good news is that we can call back these negative thoughts—the swords that we don't really want to see manifest in reality –such as those murderous thoughts we sometimes entertain. There are ways of calling them back and purifying these lesser evolved judgments. For instance, the simple statement, "Erase that!" is one way of withdrawing our sword and thereby purifying a negative thought. Forgiveness of ourselves and others, as taught by the Bible and the Course in Miracles, among others is another way to purify our negative thoughts. I'm sure you can think of other equally useful techniques for erasing negative thought projections.