Jamieson, Fausset and Brown on Jeremiah 15:19

19. God's reply to Jeremiah.

return ... bring ... again--Jeremiah, by his impatient language, had left his proper posture towards God; God saith, "If thou wilt return (to thy former patient discharge of thy prophetic function) I will bring thee back" to thy former position: in the Hebrew there is a play of words, "return ... turn again" (Jr 8:4; 4:1).

stand before me--minister acceptably to Me (De 10:8; 1Ki 17:1; 18:15).

take ... precious from ... vile--image from metals: "If thou wilt separate what is precious in thee (the divine graces imparted) from what is vile (thy natural corruptions, impatience, and hasty words), thou shall be as My mouth": my mouthpiece (Ex 4:16).

return not thou unto them--Let not them lead you into their profane ways (as Jeremiah had spoken irreverently, Jr 15:18), but lead thou them to the ways of godliness (Jr 15:16, 17). Eze 22:26 accords with the other interpretation, which, however, does not so well suit the context, "If thou wilt separate from the promiscuous mass the better ones, and lead them to conversion by faithful warnings," &c.