出埃及記 19:9

耶和華對摩西說：「我要在密雲中臨到你那裏，叫百姓在我與你說話的時候可以聽見，也可以永遠信你了。」 於是，摩西將百姓的話奏告耶和華。

And the LORD said unto Moses, Lo, I come unto thee in a thick cloud, that the people may hear when I speak with thee, and believe thee for ever. And Moses told the words of the people unto the LORD.