The verb diachōrizomai means to separate or part ways — a thorough separation. It appears in Luke 9:33 at the Transfiguration, as the cloud of glory departs and the disciples find themselves alone with Jesus, the heavenly visitors having separated from them. The moment marks the end of the mountaintop vision and the beginning of the descent to mission.
The departure of Moses and Elijah at the Transfiguration is theologically significant: Law and Prophets 'separate' from the scene, leaving Jesus alone — 'Listen to him!' commands the Father's voice. This visual theology declares the fulfillment of all that Moses and the prophets represented in the singular person of Jesus Christ. The mountaintop glory gives way to valley ministry, as Jesus prepares to 'set his face toward Jerusalem.'