The "powers of the air" that Paul writes about refers to these spiritual beings that confuse and destroy men out of hatred. Moloch is a name given to one or multiple of these creatures. Worshipped in the ancient near-east, he was the burning idol that parents would sacrifice their infants on.

This is the context Abraham was in when God asked him to sacrifice Isaac. Being in that world, Abraham was familiar with the concept of child sacrifice, but knew that God would provide a way for his promise regarding Isaac to persist. And what do you know, God stopped him before the act, merely testing his chosen man.

Moloch isn't so kind, though.