nivritteshu -- when they were completed; asva-medheshu -- his performances of the horse sacrifice; raja -- the King (Yudhishthira); yushmat -- your (Parikshit's); pitamahah -- grandfather; srinvan -- while hearing; bhagavatah -- from the Supreme Lord (Krishna); dharman -- religious principles; apricchat -- he asked; idam -- this; acyutam -- of Lord Krishna.

Your grandfather, King Yudhishthira, after completing his Asvamedha sacrifices, asked Lord Acyuta this very same question while hearing the Lord's explanation of religious principles.