Sadhana Chatushtaya

From the books written by Swami Sivananda, you will derive not only the benefit of his wisdom and knowledge of both practical and esoteric matters pertaining to yoga but also the power of his spiritual force.

Sadhana Chatushtaya or the fourfold means for salvation or the four kinds of spiritual practices is a pre-requisite to the aspirants in the path of Jnana Yoga (Vedanta) or, for that matter, in any system of evolution towards the Godhead.