Romans 4:23-25

²³ “Now not for his sake only was it written that it was credited to him, ²⁴ but for our sake also, to whom it will be credited, to us who believe in Him who raised Jesus our Lord from the dead, ²⁵ He who was delivered over because of our wrongdoings, and was raised because of our justification.”

Paul has in mind faith because faith focuses us on the object of our faith: Him who raised Jesus our Lord from the dead. Salvation is not about our works. We may try to earn salvation by keeping the law or through performing other religious duties, or even try to maintain salvation through performance. But Paul is clear: We are saved by trusting in Jesus. The full extent of this salvation, our new hearts, is tied directly to Christ’s resurrection.