Jesus brings a word of condemnation upon them by bringing to mind the false shepherds of the Old Testament.
During the time before Babylon came to conquer the Southern Kingdom of Judah God says, “‘Woe to the shepherds who destroy and scatter the sheep of my pasture!’ says the Lord. Therefore thus says the Lord, the God of Israel, concerning the shepherds who care for my people: ‘You have scattered my flock, and have driven them away, and you have not attended to them. Behold, I will attend to you for your evil doings, says the Lord’” (Jer 23:1-2).
During Jeremiah’s time, the people have chosen to follow their own plans, "and everyone will act according to the stubbornness of his evil heart" (Jer 18:12). God reacts by saying, "Behold, you trust in deceptive words to no avail. Will you steal, murder, commit adultery, swear falsely, burn incense to Baal, and go after other gods that you have not known, and then come and stand before me in this house, which is called by my name, saying, ‘We are delivered!’ – only to go on doing all these abominations? Has this house…become a den of robbers in your eyes?" (Jer 7:8-11).
But the people fail to learn from God’s wrath and Jeremiah’s words. During the time of their captivity inBabylon, the shepherds have still not learned their lesson. "Thus says the Lord God: Ho, shepherds of Israel who have been feeding yourselves! Should not shepherds feed the sheep? You eat the fat, you clothe yourselves with the wool, you slaughter the fatlings; but you do not feed the sheep. The weak you have not strengthened, the sick you have not healed, the crippled you have not bound up, the strayed you have not brought back, the lost you have not sought, and with force and harshness you have ruled them" (Ez 34:2b-4).
And when they return from exile, the prophet Zechariah speaks to them again about the same thing. After the exile, the people asked the shepherds to sacrifice to false gods in order to receive rain and vegetation. But, as God says through Zechariah: "The teraphim utter nonsense, and the diviners see lies; the dreamers tell false dreams, and give empty consolation. Therefore the people wander like sheep; they are afflicted for want of a shepherd. My anger is hot against the shepherds, and I will punish the leaders" (10:2-3a).
The book of the prophet Malachi gives us more insight into the actions of the people and their relatioship with God during this time. First, the priest shepherds are offering polluted food upon the altar and offering blind animals to God as a sacrifice (cf. Mal 1:6-8).