Good News Translation has verses 4-5 end the previous section. It fits this section on gossip much better, however. Trusting people (verse 4) deals with believing gossip; being happy with wickedness (verse 5) deals with enjoying gossip.

One who trusts others too quickly is lightminded: The person who trusts others uncritically is described as lightminded; such a person has a shallow mind. He does not give relationships serious enough thought. Compare 6.5-17. Good News Translation‘s translation is not bad here; another possibility is “Anyone who trusts people too quickly is not thinking very clearly.” To make it clear that this line is talking about gossip, it may be rendered “If you believe too easily what people say, you are not thinking very clearly.”

And one who sins does wrong to himself: Good News Translation translates this line in the second person, which works well. We could translate “If you sin, you are only making trouble for yourself.” The Greek verb translated does wrong comes from the same root as the noun rendered “wrongdoing” in 18.27, where we observed that it is an expression used of a wrong note in music (see also 9.13, where the same verb is rendered “make … misstep”).

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.