Sirach 32:21

21 Be not confident in a plain way.

Sirach 32:21 In-Context

19 Do nothing without advice; and when thou hast once done, repent not.
20 Go not in a way wherein thou mayest fall, and stumble not among the stones.
21 Be not confident in a plain way.
22 And beware of thine own children.
23 In every good work trust thy own soul; for this is the keeping of the commandments.

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