Sirach 20:19

19 An unseasonable tale will always be in the mouth of the unwise.

Sirach 20:19 In-Context

17 How oft, and of how many shall he be laughed to scorn! for he knoweth not aright what it is to have; and it is all one unto him as if he had it not.
18 To slip upon a pavement is better than to slip with the tongue: so the fall of the wicked shall come speedily.
19 An unseasonable tale will always be in the mouth of the unwise.
20 A wise sentence shall be rejected when it cometh out of a fool's mouth; for he will not speak it in due season.
21 There is that is hindered from sinning through want: and when he taketh rest, he shall not be troubled.

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