“To whom the word of the Lord came in the dayes of Iosiah the sonne of Amon king of Iudah, in the thirteenth yeere of his reigne.”
1611 King James Version (KJV)
1:2 The word - That commission from God that authorized him to his prophetic work, for the space of forty - one years successively in Judea, viz. from the 13th year of Josiah to the 11th year of Zedekiah, besides the time that he prophesied in Egypt. In the days - During his reign. Thirteenth - By which it appears that Jeremiah prophesied the last eighteen years of Josiah's reign; for he reigned thirty - one years, #2Kings 22:1|.