'Thick' in the Bible

And the Lord said to Moses, See, I will come to you in a thick cloud, so that what I say to you may come to the ears of the people and they may have belief in you for ever. And Moses gave the Lord word of what the people had said.

And when morning came on the third day, there were thunders and flames and a thick cloud on the mountain, and a horn sounding very loud; and all the people in the tents were shaking with fear.