So a mantra is not something that you utter. It is something that you strive to become because unless you become the key, existence will not open up for you. Becoming the mantra means you are becoming the key. Only if you are the key can you open the lock. Otherwise someone else has to open it for you and you have to listen to him.
Mantras could be an extremely good preparatory step. Just one mantra can do such tremendous things to people. They can be an effective force in creating something but only if they come from that kind of a source where there is a complete understanding of all that is sound. When we say “all that is sound,” we are talking about the creation itself. If a mantra comes from that kind of source, with that level of understanding and when the transmission is pure, then mantras can be an effective force.