Luke 9:33

33 As the men were leaving Yeshua, Kefa said to him, not knowing what he was saying, "It's good that we're here, Rabbi! Let's put up three shelters -- one for you, one for Moshe and one for Eliyahu."

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 They appeared in glorious splendor and spoke of his exodus, which he was soon to accomplish in Yerushalayim.

32 Kefa and those with him had been sound asleep; but on becoming fully awake, they saw his glory and the two men standing with him.

33 As the men were leaving Yeshua, Kefa said to him, not knowing what he was saying, "It's good that we're here, Rabbi! Let's put up three shelters -- one for you, one for Moshe and one for Eliyahu."

34 As he spoke, a cloud came and enveloped them. They were frightened as they entered the cloud;

35 and a voice came out of the cloud, saying, "This is my Son, whom I have chosen. Listen to him!"