To most people today, it surely seems incredible that God should raise the dead through prayer alone. However, Old Testament prophets raised people from bodily death to normal bodily action and function. And at least four specific times, Jesus did the same. In his book The Decline and Fall of the Roman Empire, Edward Gibbon reports that for more than two hundred years after Jesus' departure, his followers commonly raised the dead to useful lives. So it's reasonable to believe Jesus' command had this result in mind, not merely awakening the living from wrongdoing.
Nonetheless, raising the dead was difficult for some to accept in Jesus' day, too. Paul boldly said to King Agrippa, "Why should it be thought a thing incredible with you, that God, should raise the dead?" (Acts 26:8)
And in spite of almost universal doubt, the dead are being raised through prayer alone. One of several reports comes from a Christian Science practitioner who tells of raising a patient from diagnosed, clinical death to a normal, productive life. The patient's wife called this Christian Science practitioner for spiritual support because her husband had just been taken to a hospital for treatment of a serious heart attack. The hospital offered little hope. When she arrived, he had died. But the practitioner encouraged her to look away from the material picture to think of her husband as an eternal spiritual idea. She agreed that only God and His idea are present. Just then, the hospital reported, "He's back. We have no idea how this happened. It's a miracle." He was released, completely well, a few days later.