But, in conformity to His wisdom it was right that afterwards the Prophet should be sent back form the vision of pure Unity and that he should return… toward the separative vision. For, He created man and jinn only that they should worship Him and know Him -- and, if they remained at the degree of pure Unity, there would be none to worship Him. In this separative vision, the Worshipped and the worshipper, the Lord and the servant, the Creator and the creature are again perceived.

(Abd el-Kader)