And now may be rendered “Therefore” or “And so” (Good News Translation).

Thus says the LORD: See 2.2.

The LORD God of hosts: See 2.19.

You commit this great evil against yourselves conveys the same thought as in 42.20: “you have gone astray at the cost of your lives.” Good News Translation renders “you are doing such an evil thing to yourselves.”

To cut off from you … leaving you no remnant explains the great evil that the people of Israel had done against themselves. The meaning may be either:
(1) that all of their people will be destroyed, leaving no survivors (Revised English Bible “Why bring so great a disaster on yourselves? Why bring destruction upon Judeans, men and women, children and babies, and leave yourselves without a survivor?”) or
(2) that by going to Egypt they completely separated themselves from the people of Judah (New Jerusalem Bible “Why bring complete disaster on yourselves by cutting yourselves off from Judah—your men, women, children and babes in arms—so as to leave yourselves no remnant…?”).

The first of these interpretations seems preferable in the context. Hence Good News Translation renders “Do you want to bring destruction on men and women, children and babies, so that none of your people will be left?”

Remnant: See 6.9.

Why do you commit…?: The long rhetorical question is broken into two by Good News Translation. In many languages, however, the more natural way to express this would be with a construction such as “You are doing great evil to yourselves. You will destroy your men and women, your children and babies, so that none of your people will be left. Is that what you want to do?”

Quoted with permission from Newman, Barclay M. and Stine, Philip C. A Handbook on Jeremiah. (UBS Helps for Translators). New York: UBS, 2003. For this and other handbooks for translators see here .