Speaking through Jeremiah the prophet, God promises the coming of
shepherds “who will shepherd (the people) so that they need no
longer fear and tremble.” Specifically, a king will arise who
"shall do what is just and right in the land." Mark portrays Jesus
as the fulfillment of this prophecy, the teacher of those who were
“like sheep without a shepherd.”
The image of shepherd presents a problem for some, who resent being
compared to sheep, those docile animals instinctively following the
directions of the shepherd. The focus of the biblical image of the
shepherd, however, is not on the docility of the sheep but on the
care that the shepherd provides.
The shepherds of Israel are being castigated by Jeremiah because
they “have not cared” for the people. Jesus, on the
other hand, feels for the people and will eventually give his life
for them.
Psalm 23
is a great tribute to God as shepherd, who watches over us so that
“there is nothing (we) shall want.”
Jesus is, to use the words of Jeremiah’s prophecy, “The
Lord our justice, and it is he who is our peace.” Jesus is our
justice and our peace through the cross and his blood, so there is
nothing sheepish about Jesus, the shepherd, or about his
followers.
Notice that in Jeremiah’s prophecy God “will appoint
shepherds,” not just “a shepherd.” God appoints all of us
Christians to care for God’s people.
The Church is a sheepfold whose one and necessary door is Christ [Jn 10:1-10]. She is a flock of which God Himself foretold that he would be the Shepherd [cf. Is 40:11; Ez 34:11 ff]. Although guided by human shepherds, her sheep are nevertheless ceaselessly led and nourished by Christ himself, the Good Shepherd and the Prince of Shepherds [cf. Jn 10:11; 1 Pet 5:4], who gave His life for the sheep [cf. Jn 10:11-15].Vatican II, Constitution on the Church,
1964: paragraph 6.