koNdalvaNNanaik kOvalanAyveNNai
uNdavAyan ennuLLam kavarnthAnai
aNdarkOnaNiyarangan ennamuthinaik
kaNdakaNkaL maRRonRinaikkANAvE

Meaning:
My eyes which saw Him, who has the form of a moisture laden cloud, who has the mouth with which He ate butter when born as a yadava, who stole my heart, who is the Lord of the nithyasooris, who rests in Srirangam which is an ornament to this world, who is nectar to me, will not see anything else.

Essence:
Azhvar was living outside of Srirangam near people who were caught in the rajas and thamas guNams and he did not have access to the proper Acharyas; while those living in Srirangam were enjoying the company of Periya Perumal and having the nectar of His service. Azhvar seeing that the land of Srirangam was such that it added greatness even to Him, decided that he was not worthy of stepping in there. Thus, because of the drawbacks of those outside Srirangam he would not live them, and because of his own drawbacks he would not step into Srirangam; so he stayed near the southern banks of the Cauvery river directly under the view of Periya Perumal. Periya Perumal seeing this turned His grace on Azhvar and set His feet in his mind. Azhvar's mind then meditating on His thiruvadi moved on to enjoying His dress, His navel, the ornament around His waist, His chest, His neck, His lips, His weapons, His eyes and His whole body. Upon seeing Azhvar's mind do this and hearing his words stating this enjoyment, He decided that He wanted to invite Azhvar near Himself because of His interest in not being separated from His devotees. Since He was in archavataram He could not invite him directly; and Azhvar would not come himself. So, He had to send a representative. Since Azhvar was concentrating on Him with his mind (senRathAm enasinthaniyE, adiyEn uLLaththinnuyirE, ennuLLaththuL ninRulAkinRathE, niRaikondathennenjinaiyE), He decided to send Sri Loka Saranga Muni (LSM) whose mind was also set on Him. And so, LSM noting that izhikulaththavargaLElu memmadiyArgaLAgil thozhumineer kodumin koNmin went and got Azhvar into Srirangam. Azhvar not wishing to decline His command, came in as munivAhanar and worshipped His thiruvadi. Emperuman had come to Prahalada at his time of need and helped him and later gave him a kingdom; whereas Azhvar never had any interest in worldly matters and so He came to Azhvar and showed Himself. Azhvar then sang about His para, vyooha, vibhava and archa forms together showing his disinterest in worshipping His different forms separately. When Azhvar saw Periya Peyumal thus he realized that with Periya Perumal he had seen everything in Him and stated that He cannot enjoy anything else and even if he could his eyes could not see anything else, in this song.
Azhvar completes his songs here without referring to himself and unlike most other Azhvars, he does not complete his work speaking of his name and his place. Azhvar's experience with Him was such that he forgot his name and place and Periya Perumal has now made it such that nothing would deviate him from that experience.

koNdalvaNNanai
The subject for Azhvar's eyes.
Azhvar is speaking of His help in destroying the mere flesh of his eyes such that he could see Him.
Azhvar is speaking of His help in being in his mind in para, vyuha, vibhava and archa forms so that Azhvar can experience them all.
He is like the moisture laden dark clouds that removed Azhvar's thirst in being caught in this samsaram.
His form that destroys all difficulties.
Like a dark cloud that picked up all the water in the oceans and settled in the midst of the Cauvery.
He has the nature of the dark clouds in pouring His mercy and removing the thirst of all beings.

kOvalanAy veNNaiyuNdavAyan
The clouds simply float across the sky and pour rain anywhere; He became a yadava and mingled with them as one of them and poured His beauty on them.
When He was born as Rama, He could not steal butter; as Krishna He could do that.
Just as Sri Dasaratha prayed for a son to eat the kingdom's treasures (that is, rule the kingdom) so did Sri Nanda pray for a child to eat his treasures (the butter).
By being as one with the yadavas He showed His guNam of protecting all beings in all worlds.
By eating their butter, He shows His guNam that He would accept and enjoy anything that His devotees give to Him.

veNNaiyuNdavAyan
He got caught stealing butter and is now hiding here. If one were to smell Periya Perumal's mouth, they would be able to smell the butter even now.
Just as He was caught when stealing butter then, He is now caught by His devotees (by their love) and so the butter smell still lingers.

ennuLLam kavarnthAnai
Just as he stole butter as kOvalan, He has stolen Azhvar's heart as koNdalvaNNan.
What He did to Yasoda's heart, He has now done to Azhvar's heart.
He would steal the butter while leaving the containers alone in Ayppadi and He has now stolen Azhvar's heart while leaving his body alone.
Even great people fail when they try to place their heart in Him because of the mind's ego and its vacillatory nature. He has removed Azhvar'sdifficulties and even without Azhvar realising it He has taken over his heart.
Azhvar's heart has become the butter that He relishes.
Even after gnyAnam is born, one's mind might have ego. He has attracted Azhvar's heart by showing His beauty and glory and forever removed the ego from it by taking it over.

aNdarkOn
aNdar refers to the "idayars" and He is the leader of the Ayppadi idayars.
He is the leader of the beings of all worlds.
He was simple enough to be tied to the yadavas even while being the Lord of Brahma and all the Devas (kaNNik kuRunkayiRRAl kattuNdAnakilum eNNaRkariyanimaiyOrkkum).

aNiyarangan
After stealing Azhvar's heart He did not go to His home in the sky; instead He is resting in the temple that is an ornament to samsara.
Azhvar got to enjoy Him at a place that is so beautiful that even the nithyasooris leave the other place to come and worship Him here.

ennamuthinai
The nectar of the Devas is in an unattainable place. Azhvar's nectar is attainable to all.
The nectar that is the premier to Brahma and all other Devas and that has given immortality to Azhvar.
Not being the nectar that is attainable only to those at paramapatham and the milky ocean, but being the nectar that is attainable to everyone despite their lowly status (neesanEn niRaivonRumilEn) in this world.
Not being the nectar that even the Devas had to work hard to get, but being the nectar that anyone can get.

amuthinaikkaNdakaNkaL
The eyes that have tasted nectar.
The eyes that saw Him till the thirst was gone.
Azhvar's eyes that wouldn't see anything else even if it had not seen Him; his eyes that wouldn't see anything else even if they only saw part of Him; his eyes that have seen Him completely.

kaNdakaNkaL
Azhvar not saying en kaNkaL, makes it clear that his ego has been destroyed. Previously, he had said en kaN, ena sinthanai, adiyEnuLLam, ennuLLam, but for those who have been selected by Him to see His glory, their ego is not a dOsham like it would be for those who have not been enlightened.
The eyes that up to this time was seeing material things and having interest in them are now like a born-beggar who saw a huge treasure.

kaNdakaNkaL maRRonRinaikkANAvE
After tasting nectar would his eyes taste milk and rice (that is, things of this world).
When Azhvar said ennuLLam kavarnthAn he is talking about Him stealing his mind. When he says maRRonRinaik kANAvE he is talking about Him stealing his sight.
Azhvar has forgotten himself in the sweetness of seeing Him that he has not named himself in completing the song.
Because He is the goal and Azhvar has attained that, Azhvar has left the song with words only about Him.
Having seen Him, Azhvar's eyes would not see anything or anyone else even in the other world.
Some Acharyas have even interpreted this as that having seen Periya Perumal thus, Azhvar's eyes would not even see Him were He to show Himself again to Azhvar.
Having seen in Periya Perumal several archa roopams and several vibhava roopams, were He to show His paravyoohavibhava roopams together it would not be tasty to Azhvar's eyes.