'Depths' in the Bible

But unto you I say, and unto the rest in Thyatira, as many as have not this doctrine, and which have not known the depths of Satan, as they speak; I will put upon you none other burden.

The fifth angel blew his trumpet; and I saw a Star which had fallen from Heaven to the earth; and to him was given the key of the depths of the bottomless pit,

and he opened the depths of the bottomless pit. And smoke came up out of the pit resembling the smoke of a vast furnace, so that the sun was darkened, and the air also, by reason of the smoke of the pit.