Glorify your Son, that your Son may glorify you. The time Jesus refers to is of course the time of his death. It is what he came for. It is the climax of his mission. And his mission is to glorify the Father so that the Father may glorify the Son.
Glory means much more than just brightness or splendor, or honour or magnificence.
It is all those things together, plus holiness, goodness, in short, God-ness. The Old Testament speaks of God's Glory as being that incredible aura of holiness and burning righteousness and splendor that surrounds the Presence of the Almighty. This is the Glory that Jesus says he enjoyed with the Father before the world began. John's Gospel quite clearly teaches that Jesus understood himself to be the pre-existing One who was at God's side from eternity. If anyone doubts the true deity of Jesus they should look closely at this prayer from John 17.