Thiruvadi is Lotus feet of God. The location in the body where divine light directly expressed from Athma.

This is called origin of mind. This is the location where all saint/siddhaa meditated to attain mukthi or merge with God.

Our two pupil eyes is where divine light of God(athma) is expressed. No where else in the body we have this. Its only place to surrender to God, its place to destroy form of Mind. The divine light in pupil of eyes is called as medicine for deathless life. With current state we will not be able access the divine light. It needs guru upadesam and deekshai.