Knopf's commentary on the Didache and 1-2 Clement was originally entitled Die Apostolischen Vater. Band 1: Die Lehre der zwolf Apostel. Die zwei Clemensbriefe and was published in the Handbuch zum Neuen Testament. Erganzung-band in 1920. The volume contains introductory information for the Didache and 1-2 Clement, a translation of these texts, and accompanying critical commentary which proceeds verse by verse.

Rudolf Knopf (1874-1920) was a professor of Protestant theology at the University of Bonn. His most influential works include Das nachapostolische Zeitalter. Geschichte der christlichen Gemeinden vom Beginn der Flavierdynastie bis zum Ende Hadrians (1905) and Einfuhrung in das neue Testament (1919).
Jacob N. Cerone is a doctoral candidate at the University of Erlangen-Nuremburg. He is co-author of Daily Scriptures: 365 Readings in Hebrew, Greek, and Latin, the editor of Strack and Billerbeck's A Commentary on the New Testament from the Talmud and Midrash and Adolf von Harnack's The Letter of the Roman Church to the Corinthian Church from the Era of Domitian: 1 Clement, and co-editor of the Apostolic Fathers Greek Reader.