'Thick' in the Bible

You approached and stood at the foot of the mountain, and the mountain burned with fire to the [very] heart of the heavens: darkness, cloud and thick gloom.

“The Lord spoke these words with a great voice to all your assembly at the mountain out of the midst of the fire, the cloud, and the thick darkness, and He added no more. He wrote these commandments on two tablets of stone and gave them to me.

“But Jeshurun (Israel) became fat and kicked [at God].You became fat, thick, sleek, and obstinate!Then he abandoned God who had made him,And scorned the Rock of his salvation.