Our tutor unto Christ (παιδαγωγος υμων εις Χριστον). See 1 Corinthians 4:15 for the only other N.T. example of this old and common word for the slave employed in Greek and Roman families of the better class in charge of the boy from about six to sixteen. The paedagogue watched his behaviour at home and attended him when he went away from home as to school. Christ is our Schoolmaster and the law as paedagogue kept watch over us till we came to Christ.

That we might be justified by faith (ινα εκ πιστεως δικαιωθωμεν). This is the ultimate purpose of the law as paedagogue.

Now that faith is come (ελθουσης της πιστεως). Genitive absolute, "the faith (the time of the faith spoken of in verse Galatians 3:23) having come."

Under a tutor (υπο παιδαγωγον). The pedagogue is dismissed. We are in the school of the Master.