Mark 9:5

5So
Here καί (kai) has been translated as “so” to indicate the implied sequence of events within the narrative.
Peter said to Jesus,
Grk “And answering, Peter said to Jesus.” The participle ἀποκριθείς (apokriqeis) is redundant and has not been translated.
“Rabbi, it is good for us to be here. Let us make three shelters
Or “dwellings,” “booths” (referring to the temporary booths constructed in the celebration of the feast of Tabernacles).
Peter apparently wanted to celebrate the feast of Tabernacles or Booths that looked forward to the end and wanted to treat Moses, Elijah, and Jesus as equals by making three shelters (one for each). It was actually a way of expressing honor to Jesus, but the next few verses make it clear that it was not enough honor.
– one for you, one for Moses, and one for Elijah.”
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