4:24 For us also. If we believe our faith shall save us.
On him that raised Jesus. The same God who quickened Abraham's body, as good as dead, raised up Jesus our Lord from the dead.
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.
4:23-25 The history of Abraham, and of his justification, was recorded to teach men of after-ages; those especially to whom the gospel was then made known. It is plain, that we are not justified by the merit of our own works, but by faith in Jesus Christ and his righteousness; which is the truth urged in this and the foregoing chapter, as the great spring and foundation of all comfort. Christ did meritoriously work our justification and salvation by his death and passion, but the power and perfection thereof, with respect to us, depend on his resurrection. By his death he paid our debt, in his resurrection he received our acquittance, Isa 53:8. When he was discharged, we, in Him and together with Him, received the discharge from the guilt and punishment of all our sins. This last verse is an abridgement or summary of the whole gospel.