Jeremiah 17:10

I the Lord search the heart,.... The inward parts of it, every room and corner in it; and know the thoughts of it; all its intents, purposes, designs, contrivances, and imaginations; all the secret

I the LORD search the heart, I try the reins, even to give every man according to his ways, and according to the fruit of his doings.

Lest these hypocrites should pretend that their hearts were not departed from God, or should say, Who then can judge us if none knoweth the heart? saith God, Though no creature knoweth the heart of another fellow creature, yet I know the hearts of all creatures, I search the secret thoughts, and counsels, and designs of all my creatures; for I will judge them according to their thoughts and the secret motions and affections of their souls, according to all their ways, and the fruit of their doings. You cannot therefore mock me, and tell me your hearts are not departed from me.

Jeremiah 17:10 I the LORD search the heart, [I] try the reins, even to give every man according to his ways, [and] according to the fruit of his doings.Ver. 10. I the Lord search the heart.] Be it never so full of shifts and fetches, I cannot be deceived in it. The watchmaker must needs know every turning and winding in the watch. God is the heart maker and the heart mender; neither is there any creature, no, not any creature of the heart, that is not manifest in his sight, but all things are naked and opened before his eyes. "Naked" for the outside, and opened for the inside - dissected, quartered, and, as it were, "cleft through the back-bone," as the apostle’ s word there signifieth; so opened as the entrails of a man that is anatomised, or of a beast that is cut up and quartered. The heart and reins are taken to be the seat of the thoughts and affections, yea, of the strongest affection, namely, that which is for generation. These are a man’ s inwardest and most remote parts, so that it is hard for food or physic to come at them. Covered they are also with fat and flesh, &c., and yet they are not hid from God’ s eye, which is indeed a fiery eye, and therefore needeth no outward light. Man’ s eye is like a candle, which is first lighted, and then extinct; the angels’ eyes are like the stars, which shine indeed, and in the dark, too, but with a borrowed light, neither know they the thoughts of men’ s hearts further than they are discovered. But God’ s eye is like the sun, yea, far brighter and more piercing than that eye of the world; neither needeth he a window in man’ s breast, as Momus wished, to look in at, for every man, before God, is all window, totus totus transparens et pellucidus. This Thales and other philosophers saw and confessed. τετραχηλισμενα.

(10) According to his ways.—The Hebrew word is in the singular, his way, and the interpolated conjunction “and” is better omitted, so as to leave the last words as an explanation of what is meant by it. Jehovah, who “searches the heart,” answers the question “who can know it?” He does know, and will, in the end, judge with a perfectly righteous judgment. Men should live as in the presence of One to whom all hearts are open.

Verse 10. I the Lord search the heart] The Lord is called by his apostles, Acts 1:24, Καρδιογνωστης, the Knower of the heart. To him alone can this epithet be applied; and it is from him alone that we can derive that instruction by which we can in any measure know ourselves.

10. search … reins] See on Jeremiah 11:20. even to give, etc.] found also Jeremiah 32:19.

10. The ninth verse closes with the question: Who can know it? — This verse answers it — Only God. He can probe it to the core, and understand all its crookedness and perverseness. Ways — Literally, way.