Acquiring knowledge demands a prolonged effort to perfect karma-yoga (see previous text). One can have the enthusiasm required for such a tenacious effort only if he is convinced that it will indeed produce the desired result. Thus faith is essential to acquiring knowledge.
Shraddhavan – The faithful
As explained above, only those with faith in karma-yoga can obtain wisdom.
Tat-para samyatendriya – Dedication and discipline
One can be dedicated and disciplines only if he has faith that his practice will be fruitful.