All this is to be brought about by an overruling spiritual power that needs no assistance from human creatures; and though certain medicine-men were disposed to anticipate the Indian millennium by preaching resistance to the further encroachments of the whites, such teachings form no part of the true doctrine, and it was only where chronic dissatisfaction was aggravated by recent grievances, as among the Sioux, that the movement assumed a hostile expression. On the contrary, all believers were exhorted to make themselves worthy of the predicted happiness by discarding all things warlike and practicing honesty, peace, and good will, not only among themselves, but also toward the whites, so long as they were together. Some apostles have even thought that all race distinctions are to be obliterated, and that the whites are to participate with the Indians in the coming felicity; but it seems unquestionable that this is equally contrary to the doctrine as originally preached. Different dates have been assigned at various times for the fulfillment of the prophecy. Whatever the year, it has generally been held, for very natural reasons, that the regeneration of the earth and the renewal of all life would occur in the early spring. In some cases July, and particularly the 4th of July, was the expected time. This, it may be noted, was about the season when the great annual ceremony of the sun dance formerly took place among the prairie tribes. The messiah himself has set several dates from time to time, as one prediction after another failed to materialize, and in his message to the Cheyenne and Arapaho, in August, 1891, he leaves the whole matter an open question. The date universally recognized among all the tribes immediately prior to the Sioux outbreak was the spring of 1891. As springtime came and passed, and summer grew and waned, and autumn faded again into winter without the realization of their hopes and longings, the doctrine gradually assumed its present form—that some time in the unknown future the Indian will be united with his friends who have gone before, to be forever supremely happy, and that this happiness may be anticipated in dreams, if not actually hastened in reality, by earnest and frequent attendance on the sacred dance.