43 Combine the Lord's prayer in John, the request of the devil in Luke, the sorrowfulness unto death, and the protest against sleep, followed by the command, Sleep on, in Matthew and Mark, and all difficulty disappears. The prayer in John, in which He commends the Apostles to His Father, explains the cause of His sorrowfulness, and the prayer that the cup may pass away. It is not from Himself that the Lord prays the suffering may be taken away. He beseeches the Father to preserve the disciples during His coming passion. In the same way, the prayer against Satan in St. Luke explains the confidence with which He permitted the sleep He had just forbidden.
Source: On the Trinity (New Advent)