Jeremiah criticizes the shepherds who have not guided Israel according to the mind and heart of God. Repeatedly in the Bible we hear similar criticism of unworthy and irresponsible shepherds. God brings this history of unworthy shepherds to an end with the promise to take back responsibility for gathering the scattered sheep. When Jesus proclaims himself the Good Shepherd, he is effectively declaring his divinity: he assumes to himself God's responsibility for looking after the abandoned sheep.
God also makes the promise: "I will raise up shepherds to look after them." Jesus began this task by choosing the Twelve Apostles and giving them a share in his own healing power and his authority to cast out demons. This power and authority accompanied their proclamation of the Gospel.
God continues to choose worthy shepherds throughout the ages. There have been bad shepherds in the Church in every age, and they have grievously wounded the Body of Christ, our hope in every age lies in God's promise to take to himself the responsibility of shepherding us. In every age, Jesus the Good Shepherd continues to send his chosen Apostles. So in every age, the Church is blessed by its many saints.
Lord Jesus, raise up in Your Church worthy shepherds, filled with wisdom and grace, to lead your people along the path of holiness.