Ecclesiastes 12:9-13

Not only was the Teacher wise, but he also imparted knowledge to the people. He pondered and searched out and set in order many proverbs. The Teacher searched to find just the right words, and what he wrote was upright and true. The words of the wise are like goads, their collected sayings like firmly embedded nails—given by one shepherd. Be warned, my son, of anything in addition to them. Of making many books there is no end, and much study wearies the body. Now all has been heard; here is the conclusion of the matter: Fear God and keep his commandments, for this is the duty of all mankind.