Sirach 11:9

9 Strive not in a matter that concerneth thee not; and sit not in judgment with sinners.

Sirach 11:9 In-Context

7 Blame not before thou hast examined the truth: understand first, and then rebuke.
8 Answer not before thou hast heard the cause: neither interrupt men in the midst of their talk.
9 Strive not in a matter that concerneth thee not; and sit not in judgment with sinners.
10 My son, meddle not with many matters: for if thou meddle much, thou shalt not be innocent; and if thou follow after, thou shalt not obtain, neither shalt thou escape by fleeing.
11 There is one that laboureth, and taketh pains, and maketh haste, and is so much the more behind.

The Brenton translation of the Septuagint is in the public domain.