So far your question, the soul is fundamentally pure but he has an aptitude to come to the impure state of material contamination. He is therefore called tatastha or marginal. He has got the liberty of staying within the pure state or becoming contaminated. That is his choice. This marginal point can be understood in this way; just like you are standing on the shore of the sea. So you can remain on the land or sometimes you can jump into the water to enjoy as you will see on the beaches. So many young boys are enjoying. But that is dangerous at the same time. One who does not know swimming expertly well he may become drowned. Similarly the soul from the spiritual platform sometimes jumps over the material ocean of nescience. The Vedic knowledge gives him specific instruction how to swim over but if he is a rascal, he does not take the instruction through the bona fide representative, the spiritual master, and he becomes drowned. That is the position.
Letter to Upendra, 9 October, 1971