nirbandham tasya tam jñatva
praptam kalam prativyodhum
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
When Vasudeva saw that Kamsa was determined to kill his sister Devaki, he thought to himself very deeply. Considering the imminent danger of death, he thought of another plan to stop Kamsa.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Although Vasudeva saw the imminent danger that his wife Devaki would be killed, he was convinced of his welfare because at his birth the demigods had played drums and kettledrums. He therefore attempted another way to save Devaki.