Fabricius was born in
Leipzig, son of Werner Fabricius, director of music in the church of St. Paul at Leipzig, who was the author of several works, the most important being
Deliciae Harmonicae (1656). The son received his early education from his father, who on his deathbed recommended him to the care of the theologian
Valentin Alberti. He studied under
J. G. Herrichen, and afterwards at
Quedlinburg under Samuel Schmid. It was in Schmid’s library, as he afterwards said, that he found the two books,
Kaspar von Barth's compendium
Adversariorum libri LX (1624) and
Daniel Georg Morhof's
Polyhistor (1688), which suggested to him the idea of his
Bibliothecæ, the kind of works on which his great reputation was ultimately founded. On returning to Leipzig in 1686, he published anonymously two years later his first work,
Scriptorum recentiorum decas, an attack on ten writers of the day. His
Decas Decadum, sive plagiariorum et pseudonymorum centuria (1689) is the only one of his works to which he signs the name Faber. Fabricius then applied himself to the study of medicine, which, however, he relinquished for that of
theology; and having gone to
Hamburg in 1693, he proposed to travel abroad, when the unexpected tidings that the expense of his education had absorbed his whole patrimony, and even left him in debt to his trustee, forced him to abandon this project. In 1693 he published a doctoral dissertation
De Platonismo Philonis Judaei which contributed to
Philo of Alexandria's losing his position as an "honorary
Church Father". He therefore remained at Hamburg in the capacity of librarian to
Johann Friedrich Mayer (1650–1712). In 1696 he accompanied his patron to
Sweden; and on his return to Hamburg, not long afterwards, he became a candidate for the chair of logic and philosophy. The suffrages being equally divided between Fabricius and
Sebastian Edzardus, one of his opponents, the appointment was decided by lot in favour of Edzardus; but in 1699 Fabricius succeeded
Vincent Placcius in the chair of
rhetoric and
ethics, a post which he held until his death, refusing invitations to
Greifswald,
Kiel,
Giessen, and
Wittenberg. He died in Hamburg. The details of the life of Fabricius are to be found in
De Vita et Scriptis J. A. Fabricii Commentarius, by his son-in-law,
H. S. Reimarus, the editor of
Dio Cassius, published at Hamburg in 1737. Commenting on Psalm 123.2 of Origen's scholium, Fabricius writes; "ad locum 1 Joh v. 7 alludi ab origene non est dubitandum". ==Works==