Galatians 3:24. The law was our schoolmaster to bring us unto Christ.
The παιδαγωγός, “schoolmaster,” was not an instructor, but a trustworthy slave, to whom was committed the care of his master’s sons from the time they were six or seven years of age until puberty. “His duty was rather to guard them from evil, both physical and moral, than to communicate instruction, to cultivate their minds, or to impart accomplishments. He went with them to and from the school or the gymnasium; he accompanied them out of doors on all occasions; he was responsible for their personal safety, and for their avoidance of bad company” (Smith's Dictionary of Antiquities, s. v. Pædagogus).