When a Prapanna (one who has surrendered) is in the presence of the Lord with devotion, can they chant the Sloka “ugram vIram mahAvishnum jvalantam sarvatomukham | nrusimham bhIshanam bhadram mrutyumrutyum namAmyaham” 108 times as a mantra? Is Mantropadesam (initiation into the mantra) required for this?