Interpretation

Sattvic austerity: all three forms (bodily, verbal, mental) practiced with supreme faith (shraddha paraya), with steadfast discipline (yuktaih — balanced, integrated), and without any expectation of reward (aphalakankshabhih). The three conditions — supreme faith, steadfastness, and desirelessness — work together: faith without consistency falters; consistency without faith becomes mechanical; both without desirelessness become entangled in ego-driven performance. When all three are present, tapas becomes utterly pure and naturally effective.