He filled them with knowledge and understanding: Knowledge and understanding is literally “knowledge of understanding.” There is probably no deeper meaning here than simply knowledge and understanding; remarkably, Revised Standard Version and Good News Translation are identical here. Another way of approaching this line is “He made them [or, us] capable of learning and understanding.”

And showed them good and evil: In contrast with Gen 2.17, where God denies people the knowledge of good and evil, which they go on to obtain by disobedience, here God freely shows them good and evil. Presumably for ben Sira good and evil means “the difference between good and evil” (Good News Translation; similarly Contemporary English Version) or “what was good and what [was] evil” (New Jerusalem Bible).

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.