In The Sign of Jonas (p 330-2) Thomas Merton writes about when he sits in silence:

“Different levels of depth

First, there is the slightly troubled surface of the sea. Here there is action, I make plans. They toss in the wake of other traffic: passing liners… Where do they spring from?

Second, there is the darkness that comes when I close my eyes. Here is where the big blue, purple, green, and grey fish swim by. Most beautiful and peaceful darkness: is it the cave of my own inner being? In this water cavern I easily live, whenever I wish. Dull rumours only of the world reach me. Sometimes a drowned barrel floats into the room. Big grey-green fish, with silver under their purple scales … I close my eyes to the sun, and live on the second level, a natural prayer, peace… There is no sound. Soon even the fish are gone. Night, night. Nothing is happening… I half open my eyes to the sun, praising the Lord of glory. Lo, thus I have returned from the blank abyss …Ferns and fish return. Lovely dark green things. In the depth of the waters, peace, peace, peace. Such is the second level of waters under the sun. We pray therein, slightly waving among the fish…

Words, as I think, do not spring from this second level. They are only meant to drown there.

Third level. Here there is positive life swimming in the rich darkness which is no longer thick like water but pure, like air. Starlight, and you do not know where it is coming from. Moonlight is in this prayer, stillness, waiting for the Redeemer. Walls watching horizons in the middle of the night … Everything is charged with intelligence, though all is night. There is no speculation here … Everything is spirit. Here God is adored. His coming is recognized… This is the holy cellar of my mortal existence, which opens into the sky.

It is a strange awakening to find the sky inside you and beneath you and above you and all around you so that your spirit is one with the sky, and all is positive night.”