Matthew Poole and continuators on 1 Kings 8:38

38 What prayer and supplication soever be made by any man: or by all thy people Israel, which shall know every man the plague of his own heart , and spread forth his hands towards this house:

i. e. Either, 1. His Sin, which may be called the plague of his heart, in opposition to the other Plagues here mentioned, which Afflict onely the Body, or outward Man: So the sence is, Who by their Afflictions are brought to a true and serious sence of their worse and inward Plague of their Sins, which are most fitly called the plague of the heart, because that is both the Principal Seat of Sin, and the Fountain from whence all Actual Sins flow, Matt. 15. 19. Or rather, 2. His Affliction; for so this is Explained in the parallel-place, 2 Chron. 6. 29. (which is the more considerable, because that Book was written after this, to Explain what was dark or deubtful, and to supply what was lacking in this) when every one shall know his own sore, and his own grief; which is not unfitly called, the plague of his heart, because it was that Plague which his Heart was most Afflicted with, which pained him at the very heart; as the Phrase is, Ier. 4. 19. comp. Psal. 55. 4. which caused him most vexation or grief, which is a Passion of the Heart: and so the sence is, Who shall know, i. e. be duly and deeply sensible of his Affliction, and the hand of God in it; and his Sin as the Cause of it: for Words of Knowledge in Scripture, do very frequently note such a kind of Knowledge as affects and changeth the Heart, and reforms the whole course of a Man's Life; for which cause, men of ungodly Lives are frequently said in Scripture not to know God, or Christ, or his Word, &c. And therefore [illegible: 1+ letters]o man knows his sore in a Scripture-sence, but he who hears the rod, who turneth unto him that smiteth him, and sincerely seeketh to the Lord for Relief.