PATANJLI …
sraddha faith …means complete clarity of heart , Like a loving mother, it protects the Yogi…

Anything done as sacrifice, charity, or penance without faith in the Supreme O son of Pṛthā, is impermanent. It is called asat and is useless both in this life and the next. Lord Krishna.

. Faith directed toward spiritual life is in the mode of goodness, faith rooted in fruitive work is in the mode of passion, faith residing in irreligious activities is in the mode of ignorance, but faith in My devotional service is purely transcendental.
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ŚB 11.25.27.

Srila AC Bhaktivedanta Swami Prabhupada writes faith is unflinching trust in something sublime.

Srila BR Sridha Swami.

Faith carries on a long way .

By proper association, one can  acquire unflinching faith , and Krishna within with directs the candidate accordingly,  a Siksa Diksa , this are the traditions of  Gaudiya Vaisnavism , the history is clearly available.

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