Vasudeva and Devaki were within Kamsa prison when Lord Krsna, in His Visnu form, appeared before them as their son. He appeared from the heart of Devaki in the dense darkness of night, like the full moon rising on the eastern horizon. The newborn child had very wonderful lotus-petal eyes and bore in His four hands a conchshell, disc, club, and lotus. On His chest was the mark of Srivatsa, and on His neck the brilliant Kaustubha gem.
Vasudeva could understand that the child was the Supreme Person