Yossi Feintuch: The problem with heeding God’s voice
The actual reason for reading Genesis 21 (on the first day of Rosh Hashanah) is to inform us about the miraculous, though certainly not immaculate…, conception of Isaac that according to tradition happened on this day. The bulk of the chapter, however, is dedicated to the forced departure of Hagar and Ishmael from Abraham's domicile.