When asked how to keep out extraneous thoughts during meditation, Sri Chinmoy answered:
“There are two kinds of thoughts: good thoughts and bad thoughts. One kind is healthy and one kind is unhealthy. Unhealthy thoughts, undivine thoughts, are our enemies, whereas good thoughts, divine thoughts, are our friends. We are standing at the door to our house and somebody is knocking at the door. If it is a friend, then we will allow him to enter. If it is an enemy, we will not allow him in. But the difficulty is that we don’t know who are our friends and who are our enemies. If we open the door just a little to see who is there, immediately the enemies may force their way in. So what should we do? We shouldn’t open the door at all. We should keep the door bolted from the inside. Our real friends will not go away. They will think, ‘There must be some special reason why he is not opening the door. Since we need him and he needs us, we will wait indefinitely for him.’ They have sympathetic oneness, so they will wait indefinitely.
“But our enemies want only to bother us, to torture and destroy us. They will wait just for a few minutes, and then they will lose all patience. These enemies have not conquered pride. They will say, ‘It is beneath our dignity to waste our time here. Who needs him? Let us go and attack somebody else.’ If we pay no attention to a monkey, the monkey will eventually go away and bite somebody else. Similarly, after a few minutes our enemies will go away. Then we can open the door and welcome our dearest friends, who will be there waiting for us.”
– Sri Chinmoy