Dhairya, or steadiness, is produced by pratyahara. Pratyahara, is the restraint of the senses, the freeing of the mind from all distractions, and the keeping of it under the control of the Atma. The mind is withdrawn from whatsoever direction it may tend by the dominant and directing Self. Pratyahara destroys the six sins. (1)
The S’aradatilaka defines pratyahara as indriyanam vicaratam visayesu baladaharanam tebhyah Pratyaharo vidhiyate (pratyahara is known as the forcible abstraction of the senses wandering over their objects).