Musar do Przysłów 9:9

And the wise man said to his son, "If it should occur to you to make friends or companions, then make friends with a wise person as it is written: 'He that walks with the wise shall be wise' (Prov. 13:20). And it is said: 'Give knowledge to a wise man and he will be yet wiser' (Prov. 9:9). And so if you wish to grow in wisdom be a companion to the wise, for if you do act wisely your wise friend will praise you and not question your wisdom, and then you will know that you can rely on your wisdom. If they honor him, he will honor you; if they praise him, he will praise you. If you need his help, he will help you, and in the things you say he will declare you to be in the right. If you grow angry he will have patience with you, and you will learn from his good deeds. And be a companion to every person from whom you can learn things that will bring you to the Service of God, Blessed may He be!" And the Sages said, "If you wish to become a friend of a man get him angry with you and if he will still admit and confess the truth of what you say even in his wrath then become his companion and friend. If not, leave him. But, when you choose a friend, choose one who knows his own worth, for if he does not know himself his wisdom is of no good. Acquire a friend who will rebuke you when you do something that is not proper and who will teach you to do the good, and who will help you with his might and money — and such a friend will be faithful. But a friend who flatters you and smooths over your mistakes and errors and comforts you when you have done evil things — separate yourself from such a one.