Luke 9:33

33 And it came to pass, in their parting from him, Peter said unto Jesus, `Master, it is good to us to be here; and we may make three booths, one for thee, and one for Moses, and one for Elijah,' not knowing what he saith:

Luke 9:33 Meaning and Commentary

Luke 9:33

And it came to pass, as they departed from him
That is, as Moses and Elias departed from Christ; or "when they began to depart", as the Syriac version renders it; or "would depart", as the Arabic and Persic versions; seemed desirous of going, or made some signal or other by which the disciples perceived they were about to go; for, as yet, they were not gone;

Peter said unto Jesus, master, it is good for us to be here, let us
make three tabernacles, one for thee, and one for Moses, and one for
Elias; (See Gill on Matthew 17:4)

not knowing what he said,
nor "what to say", as Mark observes, being in a surprise, and not in a situation to consider and weigh things well, whether what he said was right and proper, or not; (See Gill on Matthew 17:4)

Luke 9:33 In-Context

31 who having appeared in glory, spake of his outgoing that he was about to fulfil in Jerusalem,

32 but Peter and those with him were heavy with sleep, and having waked, they saw his glory, and the two men standing with him.

33 And it came to pass, in their parting from him, Peter said unto Jesus, `Master, it is good to us to be here; and we may make three booths, one for thee, and one for Moses, and one for Elijah,' not knowing what he saith:

34 and as he was speaking these things, there came a cloud, and overshadowed them, and they feared in their entering into the cloud,

35 and a voice came out of the cloud saying, `This is My Son -- the Beloved; hear ye him;'