"God cannot be explained, He cannot be argued about, He cannot be theorized, nor can He be discussed and understood. God can only be lived. . . Reality must be realized and the divinity of God must be attained and lived."
Union with God is the goal of the Sufi. He speaks of certain stages of his long journey as Shariat, Tariqat, Haqiqat and Marefat of Haqiqat. He has some notion of the perils of the path and so he makes it his business to seek a guide to lead him safely through the bewildering aspects of the jungles, seas, mountains and valleys he has to cross. He does not feel that the "God within" so blithely referred to by many as their only pilot has enough chance to steer him correctly, due to it being smothered in his heart by his own ego and desire nature. So he seeks a wise man, one who has attained the Wisdom, to show him how he can also arrive at his goal. He will depend on lesser lanterns to light his way until he can reach a Murshid whose duty it is to guide him to a Perfect Master. It is well known that the journey is long, that Perfect Masters are very rare, and that few merit the grace of a Perfect Master, so seeking souls look for the help of a Sufi who has knowledge of the road. Of course none of us are really Sufis―we are simply aspirants; only one who has the wisdom is a Sufi, i.e., a God-realized one.
Sufism has never been propounded by any one man or religion. It is not a religion, it is the essence of all religions, the true spirit or mystical side of all religions—the esoteric side of exoteric religions. It goes back to the anteriority of time but undoubtedly has been revealed more clearly down through the ages. Sufis believe that there have been illuminated souls in the world at all times, and that a great wave of illumination occurs when the world-messenger, or Avatar, comes down to mankind. Hazrat Inayat Khan once said: "The true religion, to the Sufi, is the sea of Truth, and all different faiths are as its waves."
Since it is not a religion, people of any religion can become a Sufi.
In Zoroastrianism the best-known Sufi was Hatim. In the period of Daniel there was a Sufi brotherhood. Abraham, the father of great religions, was initiated in a very ancient sect of Egypt. In the time of Mohammad they were called “the brethren of purity." Christians call St. Paul a Christian and Muslims call Shams Tabriz a Muslim, but we would call them Sufis. Sometimes under the name of Sufis, and sometimes under different names, Sufis have lived in different periods of the world as sages, kings, beggars, hermits, workmen, dervishes, monks, prophets, heroes, almost anything you can name.