Their tongue is a deadly arrow is obviously a comparison equivalent to “Their tongues are like deadly arrows” (Good News Translation). Die Bibel im heutigen Deutsch is even better: “Their words are like deadly arrows.”

It speaks deceitfully (Good News Translation “they always tell lies”) explains the meaning of the first line and serves as a transition to what follows.

With his mouth each speaks may be redundant in many languages; it may be expressed more simply as “Everyone speaks…” (Good News Translation).

Peaceably is more literally “peace,” which is the normal manner by which one Israelite would greet another; see 4.10; 6.14. As there, translators can say “Each person greets his neighbor with words of peace” or “They all greet their neighbors by saying, ‘Peace to you.’ ”

In his heart is literally “in his inward part.” The same expression in the second person is translated “within you” in 4.14. In some languages it would be more natural to say “in his thinking” or “he is thinking.” But in his heart he plans may also be translated “but secretly he plans.”

Ambush as a noun is found in the Old Testament only here and in Hos 7.6, where it is rendered “intrigue” by Revised Standard Version. The imagery is the same as that of the “Arab in the wilderness” in 3.2. Good News Translation translates plans an ambush for him as “setting a trap for him.” Others have “plans to attack him unexpectedly.”

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 .