blessed is the man against whom the Lord will not count his sin.”
Here the apostle proves that Abraham was justified not by works, but by faith. Those that of all men contended most vigorously for a share in righteousness by the privileges they enjoyed, and the works they performed, were the Jews, and therefore he appeals to the case of Abraham their father, and puts his own name to the relation, being a Hebrew of the Hebrews: Abraham our father.
Commenting on Romans 4:1-8
Blessed is the man to whom the Lord will not impute sin. As he does not to those whom he justifies in Christ, and by his righteousness; for the sins of such he has imputed to his Son, as their surety; and he has bore them, took them away, having made full satisfaction for them; so that these persons will never be charged with them...
Verse 8. Will not impute sin. On whom the Lord will not charge his sins; or who shall not be reckoned or regarded as guilty. This shows clearly what the apostle meant by imputing faith without works. It is to pardon sin, and to treat with favour; not to reckon or charge a man's sin to him; but to treat him, though personally undeserving and...