The earliest evidence we have of the question of its canonicity arising in Christian tradition is in the work of Origen of Alexandria, as reported by Eusebius in his Church History. Origen listed Lamentations and the Letter of Jeremiah as one unit with the Book of Jeremiah proper, among “the canonical books as the Hebrews have handed them down,” though scholars agree that this was surely a slip.

Epiphanius of Salamis in his Panarion writes that Jews had in their books the deuterocanonical Epistle of Jeremiah and Baruch, both combined with Jeremiah and Lamentations in only one book.

Athanasius of Alexandria mentions the same, he includes the deuterocanonical Epistle of Jeremiah and Baruch as a part of the Old Testament Canon, both combined with Jeremiah and Lamentations in only one book.

Cyril of Jerusalem states in his list of canonical books “of Jeremiah one, including Baruch and Lamentations and the Epistle”

The Synod of Laodicea (4th Century) wrote that Jeremiah, and Baruch, the Lamentations, and the Epistle are canonical in only one book.

Jerome provided the majority of the translation work for the vulgar (popular) Latin translation of the Bible, called the Vulgate Bible. In view of the fact that no Hebrew text was available, Jerome refused to consider the Epistle of Jeremiah, as the other books he called apocryphal, canonical.

Despite Jerome’s reservations, the epistle is included as chapter 6 of the Book of Baruch in the Old Testament of the Vulgate. The King James Version follows the same practice, while placing Baruch in the Apocrypha section as does Luther’s Bible. In the Ethiopian Orthodox canon, it forms part of the “Rest of Jeremiah”, along with 4 Baruch (also known as the Paraleipomena of Jeremiah).