tata ÄgnÄ«dhrÄ«ye 'mÅ›a-kalayÄvatariá¹£yÄmy Ätma-tulyam anupalabhamÄnaḥ
tataḥ - therefore; ÄgnÄ«dhrÄ«ye - in the wife of NÄbhi, the son of Ä€gnÄ«dhra; amÅ›a-kalayÄ - by an expansion of My personal form; avatariá¹£yÄmi - I shall advent Myself; Ätma-tulyam - My equal; anupalabhamÄnaḥ - not finding.
This is an example of the omnipotence of the Supreme Personality of Godhead. Although He is one without a second, He expands Himself by svÄá¹Å›a, His personal expansion, and sometimes by vibhinnÄá¹Å›a, or His separated expansion. Lord Viṣṇu herein agrees to send His personal expansion as the son of MerudevÄ«, the wife of MahÄrÄja NÄbhi, who is the son of Ä€gnÄ«dhra. The á¹›tvijaḥ, the priests, knew that God is one, yet they prayed for the Supreme Lord to become the son of MahÄrÄja NÄbhi to let the world know that the Absolute Truth, the Supreme Personality of Godhead, is one without a second. When He incarnates, He expands Himself in different potencies.