Thou holdest mine eyes waking - literally, “Thou holdest the watchings of my eyes.” Gesenius (Lexicon) translates the Hebrew word rendered “waking,” “eyelids.” Probably that is the true idea. The eyelids are the watchers or guardians of the eyes. In danger, and in sleep, they close. Here the idea is, that God held them so that they did not close. He overcame the natural tendency of the eye to shut. In other words, the psalmist was kept awake; he could not sleep. This he traces to God. The idea is, that God so kept himself before his mind - that such ideas occurred to him in regard to God - that he could not sleep.
I am so troubled - With sad and dark views of God; so troubled in endeavoring to understand his character and doings; in explaining his acts; in painful ideas that suggest themselves in regard to his justice, his goodness, his mercy.
That I cannot speak - I am struck dumb. I know not what to say. I cannot find “anything” to say. He must have a heart singularly and happily free by nature from scepticism, or must have reflected little on the divine administration, who has not had thoughts pass through his mind like these. As the psalmist was a good man, a pious man, it is of importance to remark, in view of his experience, that such reflections occur not only to the minds of bad people - of the profane - of sceptics - of infidel philosophers, but they come unbidden into the minds of good people, and often in a form which they cannot calm down. He who has never had such thoughts, happy as he may and should deem himself that he has not had them, has never known some of the deepest stirrings and workings of the human soul on the subject of religion, and is little qualified to sympathize with a spirit torn, crushed, agitated, as was that of the psalmist on these questions, or as Augustine and thousands of others have been in after-times. But let not a man conclude, because he has these thoughts, that therefore he cannot be a friend of God - a converted man. The wicked man invites them, cherishes them, and rejoices that he can find what seem to him to be reasons for indulging in such thoughts against God; the good man is pained; struggles against them: endearours to banish them from his soul.