C.S. Lewis did not make up Aslan the Lion as a Christ figure out of whole cloth. From ancient times the lion had been a symbol of lordship and power and, even, specifically, of Christ, who is the Lion of Judah. The lion also represents terror and horror, and in this aspect the lion also symbolizes Christ and the fear of the Lord which is the beginning of wisdom.
Seeing lions as symbols of Christ opens up new meaning in old scripture stories. Take Daniel in the lions’ den. The message now is that if we cry to God for help He will stop even his own mouth.