I apologize for the fact that the item I refer to is in part a blurb selling Biblical software modules, but that's not why I am calling attention to it. Rather, I think, the case for reading extrabiblical Greek texts needs not only to be made but to be promoted -- and where this blurb tends to fall short, in my opinion (and I am a user of the software program promoted by it), is in its almost exclusive focus on Jewish and Christian extrabiblical texts, whereas I would push the envelope far more expansively to encompass the kinds of Greek texts explored in our subtopic, "Other Greek Texts".
Three reasons are offered for the value of studying extrabiblical Greek texts:
(1) Extrabiblical Greek writings improve our own understanding of biblical Greek.
2) Extrabiblical Greek writings give us insight into the mindset and popular beliefs of people in New Testament times.
(3) Extrabiblical Greek writings are invaluable for the serious student of history.
I was particularly amused by the opening paragraph setting forth the first reason -- it reminded me of the dismay I felt on surveying some of the English-to-Greek exercises in Machen's primer:
When I took introductory Greek classes, we had two kinds of practice sentences to translate: simple sentences from the New Testament, and simple sentences made up by the writer that never actually occurred anywhere in ancient literature. Some of the made up sentences were rather odd in hindsight such as "βάλλει τὸ ἱμάτιον αὐτοῦ ἐπὶ τοῦ λίθου” ("He throws his clothing on the stone”)—what? I’ve seen a much better trend in some Greek intro workbooks in recent years in which the authors include actual sentences from other Greek writings such as the Apostolic Fathers, the Septuagint, Josephus, or even the Enchiridion.These works give a greater context to the language and help us sharpen our understanding of koine Greek. They give us good practice.