The extraordinary abilities that exist in you can be invoked by doing samyama. Doing samyama on different aspects will give different results. Discipline for a sādhaka, is different from that of a siddha, a perfected being. A sādhaka has to be moderate in sleep, activity, and in just about everything but for a siddha there are no rules. He can do whatever he wants.
~ Gurudev Sri Sri Ravi Shankar