Luke 9:32 “But Peter and those with him were heavy with sleep; and when they were fully awake, they saw His glory and the two men who stood with Him.”
The progression here is very similar to what we find in the garden just before Jesus is taken for trial. These three disciples and Christ go up into the mountain to pray. But, the three do not continue in prayer as Christ does and therefore fall asleep. So, they really just get the last bit of this experience. The Holy Spirit brings to their minds more of it later when the gospels are written.
This is a sad commentary on spiritual sloth. The disciples could have seen more. But they fell asleep, and were quite groggy as they finally awoke.
Heavenly Father, thank You for showing us Your truth! May we as the disciples be accounted worthy to be in the secret place where Your glory is revealed. May we never count it a common thing, but always a great honor! You alone are Almighty God. We can never have enough knowledge of Your glory. This earthly rest is of no consequence when we may see Your glory. We praise You! In the Name of the Lord Jesus Christ I pray and praise You, Amen.