What is Jesus Christ mean when he said "My Father is greater than I"?

Jesus taught his disciples to pray: “Our Father which art in heaven, hallowed be thy name.” Our heavenly Father, whose name is Jehovah, is described in the Bible as being superior to his Son. For example, Jehovah is “from everlasting to everlasting.” But the Bible says that Jesus is “the firstborn of every creature.” That Jehovah is greater than Jesus, Jesus himself taught when he said: “My Father is greater than I.”
The Father’s superiority over the Son, as well as the fact that the Father is a separate person, is highlighted also in the prayers of Jesus, such as the one before his execution: “Father, if you wish, remove this cup [that is, an ignominious death] from me. Nevertheless, let, not my will, but yours take place.” (Luke 22:42) If God and Jesus are “one in essence,” as the Trinity doctrine says, how could Jesus’ will, or wish, seem different from that of his Father?—Hebrews 5:7, 8; 9:24.
Furthermore, if Jehovah and Jesus were the same, how could one of them be aware of things of which the other was not? Jesus, for instance, said regarding the time of the world’s judgment: “Concerning that day or the hour nobody knows, neither the angels in heaven nor the Son, but the Father.”—Mark 13:32.