From John Calvin’s commentary on Jeremiah 3:15:
We hence learn that the Church cannot continue without having faithful pastors to shew the way of salvation. The wellbeing of the Church then is secured, when God raises up true and faithful teachers to proclaim his truth: but when the Church is deprived of sound teachers, all things soon fall into ruin. For God, no doubt, intimates by this promise that he would not only be the deliverer of his people, so as to restore them from exile, but that he would be also their perpetual guardian after the people had returned to their own country. It hence follows, that the Church of God is not only begotten by means of holy and godly pastors, but that its life is also cherished, nourished, and confirmed by them to the end. As it is not enough for civil order to be once set up, except the magistrates continue in their office, so nothing is more ruinous to the Church than for God to take away faithful pastors.
It cannot indeed be, that people will return to God, unless prophets be first sent: but God speaks here of a continued course of instruction, and of a well regulated government in the Church, as though he had said, “I will not only give you prophets to lead you from your wanderings to me, and to restore you to the way of salvation, but I will also continually set over you sound and faithful teachers.” But we must notice, that those who preside cannot rightly discharge their office unless they are endued with wisdom. God also intimates his paternal love, when he says, that good pastors would be dear to him.
