Sirach 6:33

Ben Sira, Ecclesiasticus

31 You will wear her like a glorious robe, and put her on like a splendid crown. 32 If you are willing, my child, you can be disciplined, and if you apply yourself you will become clever. 33 If you love to listen you will gain knowledge, and if you pay attention you will become wise. 34 Stand in the company of the elders. Who is wise? Attach yourself to such a one. 35 Be ready to listen to every godly discourse, and let no wise proverbs escape you.

Date: 195-175 B.C.E.
* Dates are based on scholarly estimates

Clement of Alexandria Stromata Book 2.5

For it were strange that the followers of the Samian Pythagoras, rejecting demonstrations of subjects of question, should regard the bare ipse dixit as ground of belief; and that this expression alone sufficed for the confirmation of what they heard, while those devoted to the contemplation of the truth, presuming to disbelieve the trustworthy Teacher, God the only Saviour, should demand of Him tests of His utterances. But He says, "He that hath ears to hear, let him hear." And who is he? Let Epicharmus say: "Mind sees, mind hears; all besides is deaf and blind." Rating some as unbelievers, Heraclitus says, "Not knowing how to hear or to speak;" aided doubtless by Solomon, who says, "If thou lovest to hear, thou shalt comprehend; and if thou incline thine ear, thou shalt be wise.

Date: 195 C.E.
* Dates are based on scholarly estimates