1 Corinthians 15:7

After that, he was seen of James; then of all the apostles.

The risen Christ was seen by James, and afterward by all the apostles. That appearing to James and then to all the apostles stands in an ordered series of appearances proving the resurrection, beginning with Cephas and then the twelve, continuing with above five hundred brethren at once of whom the greater part remained alive though some had fallen asleep, then coming to James and to all the apostles, and last to Paul as one born out of due time. This series belongs to the first truth received and delivered, that Christ died for sins according to the Scriptures, was buried, and rose again according to the Scriptures.

The appearing is one of Jesus's many repeated appearances to his followers and disciples after his resurrection. Jesus showed himself to his sorrowing, heart-broken disciples, dispelling their fears and giving them gladness and joy, while at the same time the saints raised with him appeared to many declaring that the sacrifice for man was completed and that Jesus whom the Jews crucified had risen by his mighty power. These appearances, together with the appearances and conversations of the people raised from the dead with Jesus who testified that Jesus the Prince of life was risen, formed accumulating eyewitness evidence that Jesus truly rose from the dead and that his claim as the divine Son of God is true. That evidence was known to the priests and rulers and planted the truth in the minds of those willing to believe, driving the priests to fabricate and circulate the lie that the disciples stole the body.

These appearances are eyewitness evidence establishing that Christ truly rose from the dead, and with it the future immortal life of the righteous. The list belongs to Paul's testimony about witnesses to the risen Jesus, which he used as evidence to preach Jesus as the Messiah. The sight of James and the apostles stands alongside Paul's own encounter, for Paul had seen and spoken and talked with the same Christ who had died and risen as truly and really as Cephas, James, John, and the other disciples had, so he bore witness to the resurrection.