In this way all created things emanated from Brahman, and to each class and kind a definite occupation was appointed, to perform which was the duty of the class in the universal system. Thus the life of all creatures was defined, and their vocation assigned to them in such a manner that they must fulfil it even in subsequent births.[166] The orders of priests, Kshatriyas, Vaiçyas, and Çudras, were a part in the divine order of the world; the distinction between them, the nature and relative position of each, emanated from Brahman. They are, therefore, distinct steps in the development of Brahman, and, for this reason, distinct occupations are apportioned to them. Thus there now stood, side by side, among the Indians, four classes or varieties of men, separated by God, and each provided by him with a different function. Henceforth no change was possible for one class into another, no mixture of one with another could be endured. The limits drawn by God were not to be broken through. The Brahmans are nearest to Brahman; in them the essence of Brahman, the holy spirit, the power of sanctification, lives in greater force than in the rest; they emanated from Brahman before the others; they are the first-born order. In one of the latest songs of the Rigveda, the Purusha-suktas, we are told of the world-spirit: "The Brahman was his mouth, the Rajnaya (Kshatriya) his arm, the Vaiçya his thigh, the Çudra his foot." This is a parable: the Brahman was his mouth, because the Brahmans are in possession of the prayers and holy hymns; whether the arm or the mouth, strength or speech, was preferable, is a question which remains unanswered. More distinctly and with special insistance that the mouth of Brahman is the best part of him, the law book of the priests tells us: Brahman first allowed the Brahmans to proceed from his mouth; then the Kshatriyas from his arms; next the Vaiçyas from his thigh; and lastly, the Çudras from his foot.[167] The duties fixed by Brahman for the Brahmans were sacrifice, the study and teaching of the Veda, to give justice and receive it. The duty of the Kshatriyas is to protect the people; of the Vaiçyas to tend the herds, till the fields, and carry on trade; the Çudras were only pledged to serve the three other orders.[168] It is a duty for the Kshatriyas and Vaiçyas to be reverent, submissive, and liberal to the Brahmans or first-born caste. The vocation of man is to adapt himself to the existing order of the world, to fulfil the particular mission assigned to him at birth. Any rebellion against the order of the castes is a rebellion against the divine order of the world.