James 2:19

Tremble] better, 'shudder.' Even the evil spirits have a kind of 'faith'; and their faith bears fruit of a sort. It causes them profound fear: Mark 1:24; Luke 8:28. No doubt St. James has in his mind these incidents recorded in the Gospels.

20-25. The appeal to Scripture. Abraham's readiness to sacrifice his only son was the crowning act of a life of faith which began when he left home and country. By that faith he was 'justified' (i.e. acquitted at the bar of God's judgment), and called God's friend (Isaiah 41:8). So also, when Rahab received Joshua's spies and saved their lives, her faith was practical (Joshua 2:7; Hebrews 11:31; Hebrews 1 Clem 12). Rahab, though a Gentile and an outsider, was sure that the God of Israel was the one true God, and that His people would be victorious. And she had the courage of her convictions. She showed in a practical way that she was on the Lord's side, and so was rewarded by becoming an ancestress of Christ Himself after the flesh (Matthew 1:5).