It has been discussed on this forum many times how many Gospel elements were sourced from the OT and related traditions and recast as typological 'fulfillments'. The same is true of certain sections from Acts.
I recently ran across an interesting section of the Talmud that certainly seems a good candidate for the inspiration for Pentecost scene in Acts 2.
Recall that the Shavuot or Pentecost festival was linked to the Exodus story of the reception of the 10 Commandments on Mt Sinai. The story naturally had inspired extensive midrashic commentary including the tradition below:
“The Lord said to Aaron: Go into the wilderness to meet Moses” – that is what is written: “God thunders marvelously with His voice” (Job 37:5). What is “thunders”? When the Holy One, blessed be He gave the Torah at Sinai, He displayed His voice to Israel with miracles and wonders. How so? The Holy One blessed be He would speak, and the voice emerged and circulated throughout the world. ...“From the heavens, He sounded His voice to you to admonish you [and on the earth He showed you His great fire]” ... and it says: “All the people were seeing the voices” (Exodus 20:15). Voice is not written here, but “voices.” Rabbi Yoḥanan said: The voice would emerge and divide into seventy voices for seventy languages, so that all the nations could understand.
Shemot Rabbah 5:9
The '70 languages' of the '70 nations' was a common motif from the table of nations in Genesis, sons of El in Deut 32 and tower of Babel midrash.
I did condense the snippet from the Talmud as it gets wordy but essentially the 'voice of God' was seen whirling around (like wind) from every direction ('seen' implies fiery appearance) and eventually split into 70 languages to be received by every person in attendance on Mt. Sinai. So that the miracle was each person not only saw god's fiery voice but also and heard God's voice in their mother tongue. Recall Exodus says a great many nations peoples left Egypt with the Israelites. Midrash understood that to represent all nations. with each in this scene hearing the voice in their respective languages.
It is interesting, no? At some early point prior to Johanan bar Nappaha a Pentecost tradition circulated that associated God's fire, and miraculous translation of his voice into all 70 of the world's languages. Further links are that the Exodus scene ends with 'about 3000 were killed' (32:28) and Acts 2:41 in reverse typology says 'about 3000 were saved'.
The number 120 in Acts is similarly drawn from Jewish tradition; famously, 120 were required to form a quorum for city councils. The Great Sanhedrin (led by Ezra according to tradition, edited copies of the Torah for world distribution) was made up of 120. (12 X10 significant number implying completeness and governance). Lots of symbolism and typology.