PURPORT

This verse quoted from Srimad-Bhagavatam (10.44.51) refers to the killing of Kamsa by Krsna and Balarama. Vasudeva and Devaki saw their son kill the powerful demon Kamsa, and after this they were immediately released from their shackles. Balarama and Krsna then offered respects to Devaki and Vasudeva. Both father and mother wanted to embrace their sons, but they understood that Krsna and Balarama were the Supreme Personality of Godhead, and they therefore hesitated to embrace Them. Their parental love for Krsna and Balarama was therefore hampered and decreased by awe and reverence.