he would have used his mouth and explained to them in words that he studied such "methods". then these words would have been written down in a book for us the read. Why? Becasue if his miracles were simply knowing some sort of magical voodoo. This would be the most important voodoo in history. the voodoo that raises people from the dead wouldnt remain a secret and die to history. We would have magical voodoo sages raising people from the dead left and right to this very day