I will heap evils on them: this means misfortunes, “endless disasters” (Good News Translation), or “disaster after disaster” (Contemporary English Version).

I will spend my arrows upon them: see verse 42. Here spend means to use or to use up; God will shoot all his arrows at his people. He will use up all possible disasters or calamities that are available to him. This is a vivid figure for disasters, epidemics, famines, and other misfortunes. The figure may not make sense in a culture that does not know of bows and arrows; but it would not be proper to say “shoot my bullets” as a cultural equivalent. Since arrows here refers back to evils in the first line, we may simply say “I will bring on you one disaster after another to strike you,” or “I will cause all kinds of disasters to come upon you,” or “I will cause you to experience one disaster after another,” or even “I will use up all the disasters available to me to strike you with.”

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on Deuteronomy. (UBS Helps for Translators). New York: UBS, 2000. For this and other handbooks for translators see here .