'Sky' in the Bible

The Philistine said to David, "Come here to me, so I can give your flesh to the birds of the sky and the wild animals of the field!"

This very day the Lord will deliver you into my hand! I will strike you down and cut off your head. This day I will give the corpses of the Philistine army to the birds of the sky and the wild animals of the land. Then all the land will realize that Israel has a God