Jeremiah 36:2

Take thee a roll of a book
A roll of parchment, which being wrote on, and rolled up, was called a book; but books, in those times, did not consist of leaves cut and stitched together, and bound up, as our books are, but sheets of parchments being written upon, were glued together, and then rolled up; hence such writings were called volumes; which name we still retain, and give to books, though the same practice is not used: and write therein all the words that I have spoken unto thee against
Israel, and against Judah;
for though Israel was carried captive before the times of Jeremiah, and his prophecies were chiefly directed against Judah; yet as there were some of the ten tribes mixed with them, they were included in these prophecies, and therefore mentioned: and against all the nations;
such as Egypt, Edom, Ammon, and Moab, ( Jeremiah 9:26 ) ; from the day that I spake unto thee, from the days of Josiah, even unto
this day;
that is, from the time the Lord called him to prophesy in his name, which was in, the thirteenth year of Josiah, who reigned one and thirty years; and this being the fourth year of Jehoiakim, it must be the three and twentieth year of his prophesying, and the a course of full two and twenty years; see ( Jeremiah 1:2 ) ( 25:3 ) ; now all the sermons, discourses, and prophecies, he had delivered out against one and another, during this time, must all be written in one roll or book, that that they might be read. Kimchi says their Rabbins ^F14 would have it that this roll was the book of the Lamentations, called by them "Megallah", or roll.