distya te nihatah papo
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Lord Brahma said: O Supreme Lord of all lords, proprietor of the entire universe, O benedictor of all living entities, O original person [adi-purusa], because of our good fortune You have now killed this sinful demon, who was giving trouble to the entire universe.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The word purvaja is described in Bhagavad-gita (10.8): aham sarvasya prabhavo mattah sarvam pravartate. All the demigods, including Lord Brahma, are manifested from the Supreme Personality of Godhead. Therefore the original person, the cause of all causes, is Govinda, the adi-purusam.