Broichem, the high-priest of the Druids, the foster-father and chief adviser of King Brude, was probably responsible for the order, for, the Christians once admitted, he feared that his influence would be no longer supreme. Columba, however, was not in the least daunted by this inhospitable reception. He made the sign of the Cross before the barred gates and struck them strongly with his clenched fist. Bolts and bars shot back at his touch, and silently the great gates rolled open to give the Saint and his companions passage. The King, who had seen the marvel together with all his Court, was struck with fear, and went to meet Columba with fair and peaceful words. From henceforth he treated him with reverence and courtesy, confirming to him the gift of Iona, which might be considered to lie as much in his territory as in that of the Dalriadan king, and remaining throughout his lifetime a true friend and protector. It was not until some time later that he became a Christian, but the Druids could foresee the results of his friendly intercourse with the missionaries, and resolved not to lose their influence without a struggle. Their bitter enmity was to follow Columba for years, and to be the chief hindrance to his work amongst the Picts. The religion of the Druids of Caledonia differed in some degree from that of the Druids of Britain. The people were taught to worship the sun, the rivers and the forests. Certain of the streams and wells which were, said the Druid priests, under the influence of a beneficent spirit, were wholesome and good to drink, while to taste of others which they declared to be under the rule of evil spirits, would be followed by instant death. The first thing to be done was to convince the people of the falsity of their belief and to make them cease the idolatrous practices connected with it. Columba drank in their presence of the water that was supposed to be deadly, to prove to them that no evil effects would follow. The Druids pursued him wherever he went, interrupting him continually in his preaching, holding him up to the derision of the people, and misrepresenting what he said. Columba bore all their insults with patience; but when it came to trying to drown the missionaries' voices in the singing of the psalms of the Church with shouts and mocking cries, his zeal for God's glory overcame for once his meekness, and he intoned the holy chant in such a voice of thunder that his adversaries were silenced, and the King and his people trembled with fear.