姜是老的辣 Old ginger is the hottest. Older people have experience and handle matters well.
嘴上无毛，办事不牢 No hair on the lip, no firmness in the work. Said of young people who lack experience. (Officialdom Unmasked)
后生可畏 The young are to be held in awe. Confucius continued: “How do we know that those who come after will not equal those of today?” (Analects)