He will stay with you for a time: The friendship you extend to a sinner is not returned. He will remain your “friend” only as long as it is convenient for him. Most translators will feel that the pronoun He needs to be expressed with a noun phrase here. We may express it as “A sinner,” linking this verse with verse 14, or we may follow Good News Translation in expressing it as “An enemy,” linking it with verse 16. Contemporary English Version is similar to Good News Translation by rendering the whole line as “Enemies act loyal for a while.” Grammatically this line belongs with verse 14, but its thought is closer to that of verses 16-18. The Handbook suggests following Good News Translation and Contemporary English Version.

But if you falter, he will not stand by you: Good News Translation translates if you falter as “when trouble comes,” which is not quite the same thing. Trouble can come from an outside source; ben Sira is thinking of some mistake you make, some weakness you show. Make some wrong move, and your enemy will not stand by you. The negative here is emphatic in Greek. This emphasis is lost in Good News Translation. A possible alternative model for this line is “but he won’t stand by you if you make a mistake.”

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.