According to Osho, to drown in the unfathomable is to let the vast, unknowable reality - greater than mind and ego - overwhelm you, so you stop grasping and are dissolved rather than becoming a knower. What is fathomed only decorates the intellect and inflates pride; the unfathomable shatters ego. True theism is this courageous surrender into the ocean beyond the teaspoon of understanding.
Stop trying to hold the ocean in a spoon; let the big mystery wash over you and melt your little me.