The affix vuñ comes in the sense of 'this is his object of veneration' after the words 1. vāsudeva and arjunā,
This debars छ and अण् ॥ Thus वासुदेवकः, अर्जुनकः ॥
Q. The word वासुदेव being the name of a Kshatriya would have taken by the next sutra, and there is no difference here between वुन् and वुञ्, why then include the word वासुदेव in this sutra?
A. The word वासुदेव here is the name of God (in which all dwell वसति अस्मिन्) and not the designation of a Kshatriya.
By the general rule of compounds 2.2.34 a word of fewer vowels is placed first, and so Arjuna ought to have been placed first. The not doing so in this sutra indicates (jnapaka) the existence of this rule 'that a word denoting an object of reverence is placed first. ',