Sutra:
4. manthraththilum manthraththukkuLLeedAna vasthuvilum manthraprathanAna AcAryan pakkalilum prEmam ganakka uNdAnAl kAryakaramAvathu.

Meaning:
If a person develops great affection and love for this manthra, for the Lord who is the inner meaning of this manthra and for the Acharya who teaches this Thirumanthra, then this manthra will act for him.

Sri PBA Swami's Sarartha Deepikai:
In the previous choorNai, it was said that a kind and melted heart was needed for the recital of this manthra. If the question arises, whether that is sufficent, the answer is no. The manthra's recital has its effect only when there is love for the manthra, for Lord Sriman Narayana who is the true meaning of the manthra, as well as for the Acharya who out of his great kindness taught the manthra to that person. Only then will the manthra have the true effect for the person reciting it.