tÄá¹s tathÄvasitÄn vÄ«ká¹£ya
yajñaḥ sarva-gato hariḥ
yÄmaiḥ parivá¹›to devair
hatvÄÅ›Äsat tri-viá¹£á¹apam
tÄn - the demons and RÄká¹£asas; tathÄ - in that way; avasitÄn - who were determined to devour SvÄyambhuva Manu; vÄ«ká¹£ya - upon observing; yajñaḥ - Lord Viṣṇu, known as Yajña; sarva-gataḥ - who is seated in everyone's heart; hariḥ - the Supreme Personality of Godhead; yÄmaiḥ - with His sons named the YÄmas; parivá¹›taḥ - surrounded; devaiḥ - by the demigods; hatvÄ - after killing (the demons); aÅ›Äsat - ruled (taking the post of Indra); tri-viá¹£á¹apam - the heavenly planets.
The various names of the demigods — Lord BrahmÄ, Lord Åšiva, Lord Indra and so on — are not personal names; they are names of different posts. In this regard, we understand that Lord Viṣṇu sometimes becomes BrahmÄ or Indra when there is no suitable person to occupy these posts.