Note 10 at Mt. 27:9: The closest Old Testament passage to what is being quoted here is found in Zechariah 11:12-13 (see Lk.'s col., p. 469), not in Jeremiah. This looks like a human mistake on Matthew's part in citing the correct author and throws doubt on whether Matthew was really inspired in writing this gospel. There could be a number of explanations which would still maintain the inspiration and infallibility of the scriptures.

First, there are some differences between the text of Zechariah 11:12-13 and the quotation here so that it is not certain that this quotation was from Zechariah. It is possible that Jeremiah did write prophetically concerning this instance but we no longer have a copy of that manuscript.

It's also possible that Matthew cited some of Jeremiah's writings about the potter (Jer. 18:2; 19:1-2; 32:6-14) and combined them with the prophecy of Zechariah, crediting only the first writer.

There are other possibilities, including the possibility that Jeremiah may have authored some of the passages Zechariah used in his prophecy. It cannot be said emphatically what the answer to this apparent discrepancy is. However, it cannot be said emphatically that there is a discrepancy either, when other solutions are possible.