Jeremiah 31:19

Surely after that I was turned, I repented; and after that I was instructed, I smote upon my thigh: I was ashamed, yea, even confounded, because I did bear the reproach of my youth.

Surely after that I was turned I repented,.... Ephraim's prayer was answered; as he prayed he might be turned, he was; and when he was turned, then he repented, not only of sin in general, but of such sins as he had been particularly guilty of; not only of the grosser actions of life, but of inward sins, secret lusts and corruptions; even of sins of holy things, having now different sentiments, affections, and conduct: and this is what is called evangelical repentance, and is from the grace of God; springs from love; flows from a sight of God and a view of Christ; is increased by the discoveries of God's love, and is unto life and salvation; and this sort of repentance follows upon conversion; there must be first a true and real conversion before this evangelical repentance can take place:

and after that I was instructed I smote upon my thigh: as expressive of sorrow for sin after a godly sort; of indignation at it; and shame and confusion for it; and also of astonishment, at the mercy, forbearance, and long suffering of God, Ezekiel 21:12; and this humiliation follows upon spiritual instruction, which is previously necessary to it; "after it was made known to me" {u}; as the words may be rendered; what a sinful, guilty, impure, and impotent, and unrighteous creature he was; after that he became acquainted with himself, and his wretched state and condition; when instructed either by the rod, or by the word, and by the Spirit of God, in the use of both, or either; when led into the knowledge of divine things; of the love and grace of God through Christ; of the person, offices, and glory of Christ; of the way of life and salvation by him; and of the doctrines of pardon, and righteousness, and acceptance through him:

I was ashamed, yea, even confounded, because I did bear the reproach of my youth; in his conscience; the sins and follies of his youth being presented and set before him, and he convinced of them, was filled with shame and confusion at the remembrance of them; which is a common thing when a man is thoroughly awakened and converted, and is brought to true repentance and humiliation. So the Targum,

"because we have received the reproach of our sins, which were of old?''

{u} yedwh ydxaw "et postquam ostensum est mihi", Pagninus, Vatablus; "ostensum fuerit", Junius & Tremellius; "et post notum est mihi", Montanus.