"yen thIrthanE".. ?

From the Bhakti List Archives

• April 17, 1995


Mani Varadarajan says :

ovaath thuyarp piRavi utpada maRRev evaiyum,
moovaath thani muthalaay moovulakum kaavalOn,
maavaagi aamaiyaay mIn aagi maanidam aam,
thEvaathi thEva perumaa Nnen_thIrththanE.	2.8.5

I was hoping someone could shed light on why aazhvaar
addresses perumaaL as his "thIrththan" in the last line. 
What exactly is he saying? I don't know of any temple
where the deity is known as thIrththan, nor does it
seem particularly appropriate for the word to simply mean
the "sanctifier" or "sanctified". 

***

Connecting back to the "ovaath thuyarp piravi" line of thought, how about
if Nammaazhvaar is addressing Perumal as 

" yen vinai thIrthanE"

or

"yen kali thIrthanE"

- in the sense of He who ended ( theerthavan ), finished the cycle
of birth, sin, death ? , rather than the sanctifier ( sanskrit 'tIrta" )

Just a thought,

Sundar