Those who forsake the Lord will fall into its power: Even devout people may be the subject of vicious talk, but only those who are not devout, “who have abandoned the Lord,” will be “Its victims” (Good News Translation), that is, will suffer the results described in verses 19-21. This line may be rendered “But those who reject [or, abandon] the Lord will fall into the power of these cruel words” or “These cruel words will overcome those who reject the Lord.”
It will burn among them and will not be put out: The pronoun it still refers to “the tongue” last mentioned in verse 18. Good News Translation helpfully prepares for the imagery here by referring to “the fire of slander.” Such a fire will not burn until it has been lit, and Good News Translation translates with this in mind: “once the fire of slander has been lit among them, it cannot be put out.”
It will be sent out against them like a lion; like a leopard it will mangle them: There is a sudden shift of imagery here, from fire to wild animals. Good News Translation eases the transition by repeating the word “Slander.” Be sent out against them like a lion describes the effect of slander running loose among those who have abandoned the Lord; it does not necessarily imply that someone—God or anyone else—has sent out the lions. Good News Translation translates “pounce on them like a lion,” but pouncing suggests a house cat. New American Bible is excellent here with “hurl itself against them like a lion.” For lion see 4.30. To mangle something is to tear it to pieces. Contemporary English Version combines the last two lines of this verse as follows: “And these cruel words are like lions and leopards, hunting down their victims and tearing them apart.” In cultures where lions and leopards are unknown, we may use “wild animals”; for example, “And these cruel words are like wild animals that hunt down their victims and tear them in pieces.”
Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on Sirach. (UBS Helps for Translators). New York: UBS, 2008. For this and other handbooks for translators see here.