Why did resurrection have to begin with Christ?

Les explains that people like Elijah and the widow's son, and even Lazarus in Christ's earthly ministry, were not resurrected. They were merely brought back to life only to die again. True resurrection was precipitated by Christ's own resurrection, which opened the door to the whole doctrine of life after death. Les says it had to begin with the Creator Himself. Resurrection never took place until Jesus was raised from the dead. Immediately after His resurrection, to show its power and fulfill Old Testament first fruits, graves were opened around Jerusalem, and those raised went into the Holy City and appeared to many. Les reasons they had to have gone on into glory because they were resurrected, not merely raised like Lazarus to die again. Meanwhile, the Jewish leaders and Romans sealed the sepulcher because they remembered He said after three days He would rise.