John Dummelow's Commentary on the Bible - Genesis 17:1-27
The Covenant of CircumcisionThis chapter is from the Priestly document, of which it shows marked characteristics: see preface to Genesis 15.1. Ninety years old and nine] Ishmael was now thirteen years old, and Abraham probably expected no other heir. But his faith was to be put to a further test. The Almighty God] Heb. el Shaddai: the name of power shows the ability to perform what was promised. Walk before me, and be thou perfeet] i.e. always conscious of My presence, and living a pious,... read more
Expository Notes of Dr. Thomas Constable - Genesis 17:15-21
Abraham’s laugh (Genesis 17:17) may have expressed his incredulity, but it could have been a joyful response to God’s promise. [Note: See Raymond L. Cox, "What Made Abraham Laugh?" Eternity (November 1975), pp. 19-20.] Sarah’s laugh (Genesis 18:15) seems to have arisen from a spirit of unbelief. God did not criticize Abraham for laughing, but He did Sarah when she laughed. read more