And indeed, you are of a great moral character.  —Qur'an 68:4

If you were to search the word 'Sufism', you would get about a million hits in Google. Were you read every one of those pages, you would know absolutely nothing about Sufism. Not one iota.

You would know Sufi doctrine. But of Sufism you would know nothing.

If Allah was to grant you a life of a hundred thousand years, and every day from morning to night you thought about what Sufism might be, never in all that time would it ever cross your mind as to what Sufism is.

This is because Sufism is not a knowledge. You would be trying to understand with mind, what is beyond mind. There is a knowledge which is in books, and there is a knowledge which is secreted in the hearts of men.

But we know it, like you know the back of your hand. The noetic, completely ineffable, and indescribable in words. That thing that all the prophets, the saints, the gnostics, and the mystics have spoken of, since time immemorial.