Who was the angel in Gethsemane who strengthened Jesus (Luke 22:43)?
Adam (Michael) may have been the angel in Gethsemane (Remembering Christ, 12). "We know that [Jesus] lay prostrate upon the ground as the pains and agony of an infinite burden caused him to tremble and would that he might not drink of the bitter cup. We know that an angel came from the courts of Glory to strengthen him in his ordeal. And we suppose that it was mighty Michael who foremost fell that man might be. As near as we can judge, these infinite agonies, the suffering beyond compare continued for some three or four hours." (Bruce R. McConkie, “The Purifying Power of Gethsemane,” Ensign, May 1985, 9)
“As Luke records: ‘There appeared an angel unto [Jesus] from heaven, strengthening him.’ The angelic ministrant is not named. We know that on the Mount of Transfiguration ‘Moses and Elias. . . appeared in glory, and spake of his decease which he should accomplish at Jerusalem’ (Luke 9:30–31); and if we might indulge in speculation, we would suggest that the angel who came into this second Eden was the same person who dwelt in the first Eden. At least Adam, who is Michael, the archangel—the head of the whole heavenly hierarchy of angelic ministrants—seems the logical one to give aid and comfort to his Lord on such a solemn occasion. Adam fell, and Christ redeemed men from the fall; theirs was a joint enterprise, both parts of which were essential for the nation of the Father’s children.” (Bruce R. McConkie, The Mortal Messiah, 4:124–125)