Self-confidence, faith, trust, perseverance and patience are all necessary. As long as you tell yourself that it is not possible for a dervish to give you a word, or that this word cannot possibly do what he says, then, even though you were to go near that rock, you might just call out the word and find that the rock would not open. So then you might think: "It is no use. I shall go home again", or you might think: "This is a rock. How can it possibly be opened or split?" True, it will never be opened in this case: the word has no power. The word is the sword, and the sword needs an arm to wield it. The arm to wield it is faith. If there is no faith there is no arm either. The sword is there, but there is no one to wield it. Someone must be there to hold the sword, and it is faith that will hold it.