All teachers advise to meditate. What is the purpose of meditation?
We know the outer world of sensations and actions, but of our inner world of thoughts and feelings we know very little. The primary purpose of meditation is to become conscious of, and familiar with, our inner life. the ultimate purpose is to reach the source of life and consciousness.
Incidentally, practice of meditation affects deeply our character. We are slaves to what we do not know, of what we know we are masters. Whatever vice or weakness in ourselves we discover and understand its causes and its workings, we overcome it by the very knowing; the unconscious dissolves when brought into the conscious. The dissolution of the unconscious releases energy, the mind feels adequate and become quiet.