23:34

This verse uses two similes to describe the feelings or sensations of the person who is in a drunken stupor. He feels dizzy, nauseated, and unsteady. He may also toss and turn uncomfortably as he tries to sleep.

34a You will be like one sleeping on the high seas

34b
lying on top of a mast:

In Hebrew, these two lines are literally:

34a You will be like one who lies down in the heart of the sea,

34b and like one who lies down at the top of a mast.

Notice that the underlined parallel parts are identical in Hebrew. The Berean Standard Bible has used terms with similar meaning to avoid redundancy in English.

23:34a

You will be like one sleeping on the high seas: The first simile compares the drunk person to someone who lies down to sleep in a sailing ship in the middle of the ocean. It does not refer to someone who is literally lying down in the water. Some other ways to translate this line are:

You will feel ⌊dizzy⌋ , as if you are lying down in a ship ⌊during a storm⌋ .
-or-
You will feel like a person on a ship. ⌊You will turn/roll from side to side⌋ as you try to sleep.

23:34b

lying on the top of a mast: The second simile describes a specific location high above the deck of the ship. It may refer to the ropes that attach the sails to the mast (the rigging). It may also refer to a basket or small platform near the top of the mast of a sailing ship. Here a person would feel the rocking motion of the ship most strongly. Some other ways to translate this line are:

like one lying on top of the rigging (Tanakh: The Holy Scriptures)
-or-
as if you’re on top of a ship’s sails (New Century Version)
-or-
like a person hanging on to the ropes at the highest part of the ship