Sutra:
1. Mumukshuvukku aRiya vENdiya rahasyam mUnRu.

Meaning:
There are three Rahasyas that one who craves Moksha (liberation) has to know for sure.

Sri PBA Swami's Sarartha Deepikai:
A being who has lost interest in this world and has the sole wish of reaching Sriman Narayana's lotus feet is known as Mumukshu. Such a person has to most assuredly know three rahasyas. Each person has to know the nature of self, the means and the purpose. These three are explained by the Rahasyathrayam and as such mumukshus have to understand these three rahasyas. The rahasyathrayam are Thirumanthiram, Dvayam and Carama Slokam. The word mumukshu comes from the combination of mokthum icchu: That is one who desires liberation from the samsaric cycle.