Sutra:
154. prapadhyE - paRRugiREn.
155. vAsikamAgavum kAyikamAgavum paRRinAlum paRRukku izhavillai; njAnAth mOkshamAgaiyAlE mAnaSamAgak kadavadhu.

Meaning:
154. prapadhye - I am attaching myself to (I am taking refuge in).
155. It may be sufficient to pray with words or by folding one's hands. However, since the Sastras say that liberation is attained through knowledge, the attachment is taken as being done through the mind.

Sri PBA Swami's Sarartha Deepikai:
Prapadhye means I attach myself to. If one were to pray for protection with mere words alone or by folding one's hands or other forms of worship, that itself might bear fruit. However, as the Sastras say that moksha is obtained through knowledge ("tatvanjAnAt mukti:"), here the attachment is done through the mind. The essential bent of the mind that accepts His protection is the knowledge that is spoken of here.