There are various kinds of hostile forces that have the form of evil thoughts. If you want something from somebody and he does not give you what you want, what do you do? You allow undivine thoughts to enter into your mind and you tell them, "Go and fight." These thoughts are like soldiers. They go out and attack the person from whom you expected something.
Your mind is your door. You have the authority to open the door or keep it closed. In your house you allow only your friends to enter, and not your enemies. So when thoughts come to your mental door, allow only good thoughts, divine thoughts, to enter. If you allow bad thoughts to enter your mind, they will destroy your aspiration and ruin your spiritual life. When a thought enters into you, either it is from a divine world or it is from an undivine world. If your thoughts are in any way disturbing your meditation, that means they are undivine thoughts. These can be either subtle or obvious hostile forces. Or when a thought comes and tries to possess you or make you possess it, that is a hostile force. But when a thought enters into your mind and you feel that you are expanding, you can know that it is a divine thought.
If you see a garden, you are consciously delighted with its outer beauty and inner beauty. But you are not bound by the garden. It is not capturing you and you are not trying to bind it. While you are looking at the garden you are feeling that the fragrance of the flowers is spreading all around you. That is what a divine thought is like. So whenever a thought wants to enter into you, first see whether that thought is going to bind you or whether it is going to enlarge you or be enlarged by you. The thought that can bind you or be bound by you is an undivine thought, a hostile force. The thought that can expand you, and that you can expand with your aspiring consciousness, is a divine thought.From:Sri Chinmoy,Mind-confusion and heart-illumination, part 1, Agni Press, 1974
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