Mudhal Azhvargal are the first three Azhvars to appear in this world. They are Poygai
Azhvar, Bhoothaththazhvar and Peyazhvar. They were born in three different flowers in the divyadesams of Kanchi, Mallai and Mayilai. Having been given the flawless
knowledge by the Lord they went from one place to another every day and experienced Him.

One time the Lord decided to bring them all together in the divyadesam of
Thirukkovalur. It was a dark and stormy night. First Poygaiyazhvar arrived and saught
shelter in the ashrama of Mrugandu Maharishi. He was resting in the idai kazhi (the area between the front and back of the house) area. Soon after Bhoothaththazhvar arrived to the same place. They both were able to sit comfortably in that place. Then came Peyazhvar and the three were able to stand only in the narrow area. Shortly after that the three Azhvars realized that a fourth person was in the place and pushing against all of them.

Realizing it was the Lord Himself, Poygaiyazhvar lit a lamp through a verse – “vaiyam
thagaLiyA vArkadalE neyyAga veyya kadhirOn viLAkkAga” – this became the first
verse of Mudhal Thiruvandhadhi. In this verse, Azhvar made this world the cup, the
ocean as the ghee and the Sun as the light.
Bhoothaththazhvar lit another lamp through a verse – “anbE thagaLiyA ArvamE neyyAgainburugu sindhai iduthiriyA” – this became the first verse of Irandam Thiruvandhadhi. In this verse, Azhvar made his love as the cup, his passion as the ghee and his thought as the lamp.
In this light, Peyazhvar saw the Lord with His divine consort and sang the verse
thirukkaNdEn pon mEni kaNdEn“. This became the first verse of Moonram
Thiruvandhadhi.

All three Azhvars thus saw the Lord in the narrow area of the ashrama and sang the first pasurams of the Nalayira Divyaprabandham.