1 Enoch 71:5
4 He revealed to me all the secrets of the ends of heaven, and all the chambers of the stars and luminaries, from where they emerge before the holy ones. 5 My spirit was taken into the highest heaven where I saw a structure built of crystals with tongues of living fire between them. 6 I observed the girdle of fire encircling this fiery house, with streams of living fire on all four sides.
Acts 2:3
1 Now when the day of Pentecost had come, they were all together in one place. 2 Suddenly a sound like a violent wind blowing came from heaven and filled the entire house where they were sitting. 3 And tongues spreading out like a fire appeared to them and came to rest on each one of them. 4 All of them were filled with the Holy Spirit, and they began to speak in other languages as the Spirit enabled them.
Notes and References
"... There are some early Jewish writings that could show some awareness of or be inspired by the Old Testament image of ‘tongues of fire’ being associated with a divine theophany in a heavenly or earthly temple. The phrase ‘tongues of fire’ also occurs in these Jewish passages. Perhaps a parallel to the fiery ‘tongues’ of Acts 2:3 is 1 Enoch 14:8–25. There Enoch ascends in a vision to the heavenly temple. Enoch comes to the wall of the outer court that was ‘surrounded by tongues of fire’, and he ‘entered into the tongues of fire’ (14:9–10). He then enters through the holy place and is able to peer into the holy of holies, which was ‘built with tongues of fire’ (14:15). Likewise, in 1 Enoch 71:5 Enoch sees a temple-like ‘structure built of crystals; and between those crystals tongues of living fire’. Thus, the ‘tongues of fire’ form part of the heavenly temple and contribute to the overall effect of the burning theophany in the holy of holies, where ‘the flaming fire was around about him, and a great fire stood before him’ ..."
Beale, G. K. The Temple and the Church’s Mission: A Biblical Theology of the Dwelling Place of God (p. 247) InterVarsity Press, 2004