וַתִּקְרְב֥וּן וַתַּֽעַמְד֖וּן תַּ֣חַת הָהָ֑ר וְהָהָ֞ר בֹּעֵ֤ר בָּאֵשׁ֙ עַד־לֵ֣ב הַשָּׁמַ֔יִם חֹ֖שֶׁךְ עָנָ֥ן וַעֲרָפֶֽל׃
And ye came near and stood under the mountain; and the mountain burned with fire unto the heart of heaven, with darkness, cloud, and thick darkness.
Targum Jonathan on Deuteronomy
And you drew near, and stood at the lower part of the mount, and the mountain burned with fire, and its flame went up to the height of the heavens, with darkness, clouds, and shadows.