Sant Kabir was a weaver of Kashi, famous for his plain and simple couplets. Even while weaving cloth he sang bhajans and taught people the truth.
It is said that some people came to him every day to criticise his practice and his words. His disciples would get angry at them, but Kabir stayed calm.
One day the disciples asked why he did not get angry with them. Kabir smiled and recited his couplet: keep your critic close, build him a hut in your courtyard, for without water or soap he cleanses your nature.
He explained that the one who points out our faults purifies our character without soap or water. So criticism should be seen not as enmity but as a chance to improve.