Adam Clarke's Commentary on the Bible

Verse 23 (James 2:23)

The scripture was fulfilled - He believed God; this faith was never inactive, it was accounted to him for righteousness: and being justified by thus believing, his life of obedience showed that he had not received the grace of God in vain. See the notes on Genesis 15:6 ; Romans 4:3 ; (note); Galatians 3:6 ; (note); where this subject is largely explained.

The friend of God - The highest character ever given to man. As among friends every thing is in common; so God took Abraham into intimate communion with himself, and poured out upon him the choicest of his blessings: for as God can never be in want, because he possesses all things; so Abraham his friend could never be destitute, because God was his friend.

- Adam Clarke's Commentary on the Bible