The death of Christ is the proper cause of justification, or means of atonement, according to St. Paul; the resurrection of Christ is only the mediate or secondary cause of it. The atoning efficacy lay in His death, but the proof of that efficacy—the proof that it was really the Messiah who died—was to be seen in the Resurrection. The Resurrection, therefore, gave the greatest impulse to faith in the atoning efficacy of the death upon the cross, and in this way helped to bring about justification. Comp. especially 1Co_15:17, “If Christ be not raised, your faith is vain; ye are yet in your sins”—i.e., you have no guarantee that your sins have really been remitted; if the death of Christ had not been followed by His resurrection, the inference would have followed that it was merely the death of an ordinary man, and without any special saving efficacy.
BF you have just proven what I have been trying to get you to understand.
Christ's death saved no one but it did atone for the sins of all mankind. He was the propitiation for the sins of the Whole World.
The doctrine of justification by faith, which is so nobly proved in the preceding chapter, is one of the grandest displays of the mercy of God to mankind. It is so very plain that all may comprehend it; and so free that all may attain it. What more simple than this? Thou art a sinner, in consequence condemned to perdition, and utterly unable to save thy own soul. All are in the same state with thyself, and no man can give a ransom for the soul of his neighbor. God, in his mercy, has provided a Savior for thee. As thy life was forfeited to death because of thy transgressions, Jesus Christ has redeemed thy life by giving up his own; he died in thy stead, and has made an atonement to God for thy transgressions; and offers thee the pardon he has thus purchased, on the simple condition, that thou believe that his death is a sufficient sacrifice, ransom, and oblation for thy sin; and that thou bring it as such, by confident faith, to the throne of God, and plead it in thy own behalf there. When thou dost so, thy faith in that sacrifice shall be imputed to thee for righteousness; i.e. it shall be the means of receiving that salvation which Christ has bought by his blood. Clarke Romans 4:25
The condition for our salvation is faith in the risen son