“And therefore it was imputed to him for righteousness.”
King James Version (KJV)
4:23 On his account only - To do personal honour to him.
4:24 But on ours also - To establish us in seeking justification by faith, and not by works; and to afford a full answer to those who say that, to be justified by works means only, by Judaism; to be justified by faith means, by embracing Christianity, that is, the system of doctrines so called. Sure it is that Abraham could not in this sense be justified either by faith or by works; and equally sure that David (taking the words thus) was justified by works, and not by faith. Who raised up Jesus from the dead - As he did in a manner both Abraham and Sarah. If we believe on him who raised up Jesus - God the Father therefore is the proper object of justifying faith. It is observable, that St. Paul here, in speaking both of our faith and of the faith of Abraham, puts a part for the whole. And he mentions that part, with regard to Abraham, which would naturally affect the Jews most.
Ro 4:22 And therefore it was imputed to him for righteousness. The faith that secures God's righteousness is a faith that does not falter, but accepts and acts upon God's promise.