vibudhya tam balaka-marika-graham
caracaratma sa nimiliteksanah
anantam aropayad ankam antakam
yathoragam suptam abuddhi-rajju-dhih
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Lord Sri Krsna, the all-pervading Supersoul, lying on the bed, understood that Putana, a witch who was expert in killing small children, had come to kill Him. Therefore, as if afraid of her, Krsna closed His eyes. Thus Putana took upon her lap Him who was to be her own annihilation, just as an unintelligent person places a sleeping snake on his lap, thinking the snake to be a rope.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
In this verse there are two perplexities. When Krsna saw that Putana had come to kill Him, He thought that since this woman was present with motherly affection, although artificial, He had to offer her a benediction. Therefore He looked at her with a little perplexity and then closed His eyes again. Putana Raksasi also was perplexed. She was not intelligent enough to understand that she was taking a sleeping snake on her lap; she thought the snake to be an ordinary rope. The two words antakam and anantam are contradictory. Because of not being intelligent, Putana thought that she could kill her antakam, the source of her annihilation; but because He is ananta, unlimited, no one can kill Him.