John Trapp on Jeremiah 31:19

Ver. 19. Surely after that I was turned, I repented] After that I had turned ſhort again upon my ſelf, as thoſe Penitents, 1 King. 8.47. as Manaſſeh, the Publican, Luke 18. and that Prodigal, Luke 15.17.

And after that I was inſtructed] Poſt quam oſtenſum fuerit mihi, Tremel. In gloſſ. marginal. Homer hath it oft [non-Latin text not transcribed], he ſmot on his thigh. Tully hath the like, lib. 3. Tuſcul. After that I knew my ſelf, or rather was made known to my ſelf, ſc. by mine afflictions ſanctified: for Schola crucis, ſchola lucis: Afflictions are thoſe pillulae lucis, that ſerve notably to clear the ſouls eye-ſight.

I ſmot upon my thigh] Sicut mulierculae in puerperio facere ſolent, ſaith Luther: as travelling women uſe to do. Tis a token of greateſt grief. See Ezek. 21.12.

I was aſhamed, yea even confounded] Abaſhed and abaſed to the utmoſt: my ſorrow was deep and downright.

Becauſe I did bear the reproach of my youth] i. e. The brunt and burthen of my reproachful practiſes in my youth. See Job 13.26. Pſal. 25.7.