I lived in solitude, and devoted myself to ascetic exercises, in which I sought to purify my soul, improve my character, and cleanse my heart. In all things I followed the teachings of the mystics whose books I had read, hoping that I should have a direct encounter with God. In order to be alone, I sometimes Went to the nearby mosque, and climbed to the top of the minaret, shutting myself in from dawn until dusk. I experienced ecstasy only occasionally; but I never ceased to yearn and strive for it.
I continued in this manner for ten years; and during this time many deep and important things were revealed to me. I shall say a little of what I learnt, so that others may be helped, I learnt that the mystics, above all people, walk on the path of God. And I learnt that their life is the best life, their spiritual method is the soundest spiritual method, and they attain the greatest purity of character. Indeed, if the intellect of the intellectuals, the learning of the learned, and the scholarship of the scholars, were combined, they still could not find a way of improving the life and the character of the mystics.
To the mystics all movement and all rest, whether physical or mental, enlighten the soul; all actions bring light from the lamp of divine revelation. And there is no other light anywhere on earth, from which the soul may be enlightened.
(Imam al-Ghazali)