As recounted by Charles Spurgeon in sermon #108:

Oh! to have heard Luther pray!

Luther, you know, when Melancthon was dying, went to his death-bed, and said, “Melancthon, you shall not die!”

“Oh,” said Melancthon, “I must die! It is a world of toil and trouble.”

“Melancthon,” said he, “I have need of thee, and God’s cause has need of thee, and as my name is Luther, thou shalt not die!”

The physician said he would.

Well, down went Luther on his knees, and began to tug at death. Old death struggled mightily for Melancthon, and he had got him well nigh on his shoulders.

“Drop him,” said Luther, “drop him, I want him.”

“Ho,” said death, “he is my prey, I will take him!”

“Down with him,” said Luther, “down with him, death, or I will wrestle with thee!”

And he seemed to take hold of the grim monster, and hurl him to the ground, and he came off victorious, like Orpheus with his wife, up from the very shades of death. He had delivered Melancthon from death by prayer!

“Oh,” say you, “that is an extraordinary case.” No, beloved, not one-half so extraordinary as you dream. I have men and women here who have done the same in other cases; that have asked a thing of God, and have had it; that have been to the throne, and showed a promise, and said they would not come away without its fulfillment, and have come back from God’s throne conquerors of the Almighty; for prayer moves the arm that moves the world.