1. Here is the good work which God undertakes to fulfil in them. He that is their Redeemer, in order to that, will be, (1.) Their instructor: "I am thy God that teaches thee to profit, that is, teaches thee such things as are profitable for thee, things that belong to thy peace." By this God shows himself to be a God in covenant with us, by his teaching us (Heb. viii. 10, 11); and none teaches like him, for he gives an understanding. Whom God redeems he teaches; whom he designs to deliver out of their afflictions he first teaches to profit by their afflictions, makes them partakers of his holiness, for that is the profit for which he chastens us, Heb. xii. 10. (2.) Their guide: He leads them to the way and in the way by which they should go. He not only enlightens their eyes, but directs their steps. By his grace he leads them in the way of duty, by his providence he leads them in the way of deliverance. Happy are those that are under such a guidance!