Jesus Christ likes mountains.
The Bible tells us Jesus Christ prayed on mountains, preached on mountains, performed miracles on mountains, called and sent his disciples on a mountain, and was tempted by Satan on a mountain.
In Mark 9, Jesus Christ is on a mountain with 3 of his disciples. Mark tells us that on the mountain Jesus was "transfigured before them and his clothes became radiant, intensely white, as no one on earth could bleach them." In a moment, the glory of Jesus Christ was revealed to Peter, James, and John and his eternal glory radiated before them.
Moreover, Moses and Elijah, two men who lived centuries earlier, appear with Jesus and talk with him on top of the mountain. This was an incredible sight for the disciples to witness. In that moment they were catching a glimpse of the glory of the Son of God. They were seeing him for a brief moment in his divine glory. He radiated the holiness and beauty of God as he conversed with two great leaders of the Old Testament.
Then, after they heard the voice of God the Father command them to listen to Jesus Christ, Elijah and Moses disappeared and the radiating glory of Christ vanished. They descended the mountain together and Jesus continued his ministry of teaching and healing.
Reflecting on this amazing story, it's interesting to think about it in light of the life of Moses and Elijah. In Exodus, Moses ascended a mountain and met with God and received the Law. However, when he came down the mountain he confronted the evil and apostasy of the people of God and the idolatry of the golden calf. Moses left Sinai to confront sin and evil.
Likewise, Elijah spent 40 days and 40 nights on top of a mountain. He enjoyed communion with God. Yet, God commanded him to leave his mountain-top solitude to confront paganism and sin. Elijah came down the mountain bringing with him the wrath of God against evil and iniquity.
Similiarly, Jesus Christ will descend the mountain and confront sin and death on another hill - Calvary. He will go there dragging his cross as a King who conquers by the cross. He will confront sin and evil in a way that Moses and Elijah could not. Jesus Christ will confront it and destroy it forever through his sacrificial death on the cross. Because of his atoning death, God's people have the promise that sin is conquered and death is defeated. On Calvary the glory of God's plan to redeem sinners is revealed through the death of God's only Son. That victorious death is applied to you through the work of God's Holy Spirit as you put your faith in Jesus Christ as your only hope for salvation and forgiveness.