Two Children and Two Covenants (Galatians 4:21-5:1)

Sarah laughed when she heard that she was going to have a son. The competing heir of Abraham’s house, named Ishmael, also laughed at Isaac. The Lord tells Abraham to send away Ishmael for laughing at Isaac. Why is it permissible for Sarah to laugh, but not Ishmael? What are the implications of Ishmael being banished from the house of Abraham? If you are interested in hearing the answer to these questions please stay tuned as we hear, "Two Children and Two Covenants."