NUM61 [Judah b. Tema] used to say: … the man of fifty is [of the age] to [give] counsel; Pirkei Avot, Perek V, mishnah 24. This too is implied in Scripture: The Levites were to start their training for sacred service at twenty-five, and actual work at thirty. But "from the age of fifty years," says Scripture, "he [the Levite] shall withdraw from the corps of the work and serve no more, but shall minister to his brethren…" [this verse]. How shall he minister to them? – – by giving them his wise counsel how they can best do their work, and so on. For (R. Bahya remarks) as the flesh grows too weak to bear the burden of physical labor as before, the intelligence grows clearer to foresee consequences accurately; then is he eminently suited to give counsel. And, says M'iri, "his advice will be sound; for good advice requires two things--human intelligence, and experience gathered in the course of time; as the ethical philosophers have said, the days must bring wisdoms." (Musare haPhilosofim, Frankfurt-am-Main 1896, I 10, 22 quotes in the name of Aristotle, "The days will teach you wisdom.") At fifty a man has already experienced a great deal, and his mental powers are yet in full strength… Thus his counsel is purified wisdom…" (A reverse interpretation has also been suggested: even at fifty a person should still have the good sense to seek advice when he needs it.)