Kamsa was astonished because the goddess Durga had become the daughter of Devaki. Since Devaki was a human being, how could the goddess Durga become her daughter? This was one cause of his astonishment. Also, how is it that the eighth child of Devaki was a female? This also astonished him. Asuras are generally devotees of mother Durga, Sakti, or of demigods, especially Lord Siva. The appearance of Durga in her original eight-armed feature, holding various weapons, immediately changed Kamsas mind about Devakis being an ordinary human. Devaki must have had some transcendental qualities; otherwise why would the goddess Durga have taken birth from her womb? Under the circumstances, Kamsa, struck with wonder, wanted to compensate for his atrocities against his sister Devaki.