[Advaita-l] Rudra Prashna question

[Venkata sriram P via Advaita-l]

.......
According to that Mantra also the grammatical form should be Om Namo
Bhagavate Rudraaya Vishnave Mrutyor Me Paahi
...........
 
The vaidika vAk is "apaursheyam" hence one has no right to change
the forms and it has to be understood "as it is".  Without studying
the prAtIshAkhya and chandas shAstra, one shouldn't change the
vibhaktis out of one's own will.  
 
There are 4 classifications of vaidika padAs viz., aspruSTa, ISatspruSTa,
spruSTa and ardhaspruSTa. 
 
For  certain padAs, the vibhakti is "antar-bhAga" ie., hidden in "a-spaSTa" swarupa which should be understood properly with the help of Acharya.  
 
Here, in case of this mantra, it is understood to be in the form of panchami vibhakti only however the pada is "mrutyur-mE-pAhi".
 
regs,
sriram