Reference for Pirkei Avot 4:3

הוּא הָיָה אוֹמֵר, אַל תְּהִי בָז לְכָל אָדָם, וְאַל תְּהִי מַפְלִיג לְכָל דָּבָר, שֶׁאֵין לְךָ אָדָם שֶׁאֵין לוֹ שָׁעָה וְאֵין לְךָ דָבָר שֶׁאֵין לוֹ מָקוֹם:

He was wont to say: Do not underestimate any man, [saying: "How can he hurt me?"] and do not "distance" any thing, [saying: It is unlikely to happen and need not be worried about]. For there is no man who does not have his moment and there is no thing that does not have its place.

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