To compel them to listen to the warning, he asks them, Your fathers, where are they! What became of those who paid no heed to the admonitions of the prophets? Have they not suffered dire calamities and perished miserably?
And the prophets, do they live forever? They can teach and threaten no longer. It is true that the seers who warned your fathers are no more, but did not their words come true (see Zechariah 1:6)? Jerome referred these words to the false prophets, resting, doubtless, on Jeremiah 37:19.
But it is more natural to refer them to the "former prophets" mentioned above and in the following verse.