The old preachers used devices called types and the struggle between Ishmael and Isaac is a classic to represent the flesh and the Spirit battling.
Through Abraham’s story with Ishmael, we learn that we cannot be saved by works but only by trusting in God’s works done for us. Then impossible things can happen!
Faith, Abraham, Work, Impossible, Faith Vs. Works
Abraham, Pt. 5
The Life of Abraham, Part 5 of 10.