Charles H. Spurgeon on Psalms 90:11

Who knoweth the power of thine anger? etc. This he utters, 1. By way of lamentation. He sighing forth a most doleful complaint against the security and stupor he observed in that generation of men in his time, both in those that had already died in their sins, as well as of that new generation that had come up in their room, who still lived in their sins; oh, says he, `Who of them knoweth the power of thine anger?' namely, of that wrath which followeth after death, and seizes upon men's souls for ever; that is, who considers it, or regards it, till it take hold upon them? He utters it, 2. In a way of astonishment, out of the apprehension he had of the greatness of that wrath. "Who knoweth the power of thine anger?" that is, who hath or can take it in according to the greatness of it? which he endeavours to set forth, as applying himself to our own apprehension, in this wise, Even according to thy fear, so is thy wrath. Where those words, "thy fear" are taken objective, and so signify the fear of thee; and so the meaning is, that according to whatever proportion our souls can take in, in fears of thee and of thine anger, so great is thy wrath itself. You have souls that are able to comprehend vast fears and terrors; they are as extensive in their fears as in their desires, which are stretched beyond what this World or the creatures can afford them, to an infinity. The soul of man is a dark cell, which when it begets fears once, strange and fearful apparitions rise up in it, which far exceed the ordinary proportion of worldly evils (which yet also our fears usually make greater than they prove to be); but here, as to that punishment which is the effect of God's own immediate wrath, let the soul enlarge itself, says he, and widen its apprehension to the utmost; fear what you can imagine, yet still God's wrath, and the punishment it inflicts, are not only proportionable, but infinitely exceedingly all you can fear or imagine. "Who knoweth the power of thine anger?" It passeth knowledge. —Thomas Goodwin.