The immediate source of the quotation is Zechariah 11:12-13. In that chapter Zechariah predicts the end of God’s covenant with the Jewish nation.
We should have the utmost confidence in the word of the Lord and in the fulfilment of all its prophecies, however obscure they seem to us before their fulfilment. Time and again the Lord has proved that his word is perfectly fulfilled, and those prophecies whose fulfilment is yet future, can be trusted not to fail. The word of God cannot be broken.
Did Judas know of this prophecy, or of Psalm 69:25 or Psalm 109:6? Peter probably would have known these by heart, perhaps Judas also. What difference would it have made to Judas to know his acts of betrayal were prophesied beforehand? Would he blame God for what he did? No, he knew that it was his desires that had led him. He could detect within himself the lust for the thirty of silver. He could sense the comparatively small value he had set on the Messiah. Every step he had taken was his step. No one had forced him to do it. And yet he would be all the more horrified to find out that all this had been written in advance, long ago: this was his divinely appointed destiny. The sense of sin is more than he can bear and he ends his life and perishes just as Scripture had said he would.
But what do we make of the fact that Matthew attributes this prophecy not to Zechariah, but to Jeremiah? One suggests that Matthew had a slip of memory, but to say that is to put all inspiration of Scripture in question. Another says that a scribe has remembered Jeremiah’s prophecy about the potter and wrongly changed the attribution, but, since this is the universal reading, to say this is to cast doubt on the preservation of Scripture. Some argue that Zechariah’s prophecy is a fuller development of the prophecy of Jeremiah 18 and 19, but Matthew fulfilment appears to make this impossible. Some explain this by saying that the prophets were grouped together and named by the first book in the group – Zechariah being in the group which had Jeremiah first. Hendriksen offers what he calls an incomplete solution, to the extent that a solution is possible. He relates Jeremiah 19 to the fulfilment of Matthew 27:8 – ‘Wherefore that field was called, The field of blood’ – for Jeremiah speaks there of Tophet, the valley of the son of Hinnom (where human sacrifices had been offered (Jeremiah 7:31-32)), where ‘the field of blood’ was said to be located. That was a place for burial (Jeremiah 19:11; Matthew 27:7). Hendriksen concludes that two prophecies are referred to, and the major prophet is named without naming the lesser prophet, Zechariah.