Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: "People will remain in goodness as long as knowledge comes to them from their elders and their forebears; and when it comes to them from their young ones, they are ruined."
Shu'bah narrated it thus from Abu Ishaq, from Zayd bin Wahb, and Zayd bin Hibban corroborated him.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8559