Here's my set of concentric circles on Koine Greek and its close relatives with a bit of commentary and some resources for each in Greek (where readily available), moving out from the centre:
- LXX and NT : there's plenty already around on this, so suffice it here to note the (probably) lesser known volume (only one of a projected set) by Henry St. John Thackeray, A Grammar of Old Testament Greek according to the Septuagint (Cambridge, 1909). (Due to be superseded by current projects on this front, but still useful.)
It is worth bearing in mind that there are gradations of language/register, even within this body of literature. Things like Greek Jeremiah, or the gospel of Mark, are less refined than Greek Isaiah or Proverbs and the gospel of Luke. Within the "Apocrypha", too, a continuum can be seen: Tobit and Judith are relatively simple; the additions to Esther more "literary", and 3 and 4 Maccabees are getting much closer to "Attic".
- Apostolic Fathers : as they're usually called. I'm not sure about the proximity of the Greek, but I find it comfortably close to LXX/NT. The two-volume Loeb edition by Kirsopp Lake is on Archive.org:
- Volume 1 includes I. and II. Clement, Ignatius, Polycarp, the Didache, and Barnabas
- Volume 2 includes the Shepherd of Hermas, the Martyrdom of Polycarp, and the Epistle to Diognetus
- Josephus : may be Atticizing, but still quite readable for those accustomed to LXX/NT (moreso than Philo, in my experience anyway). All of the Loeb volumes are (now) available at Archive.org:
- Volume 1: The Life, Against Apion
- Volume 2: Jewish War, Books 1-3
- Volume 3: Jewish War, Books 4-7
- Volume 4: Jewish Antiquities, Books 1-4
- Volume 5: Jewish Antiquities, Books 5-8
- Volume 6: Jewish Antiquities, Books 9-11
- Volume 7: Jewish Antiquities, Books 12-14
- Volume 8: Jewish Antiquities, Books 15-17
- Volume 9: Jewish Antiquities, Books 18-19
- Volume 10: Jewish Antiquities, Book 20 + Indices
- James Hope Moulton and George Milligan, The Vocabulary of the Greek Testament Illustrated from the Papyri and other Non-Literary Sources (Hodder & Stoughton, 1929). As the title suggests, this gives access to non-literary sources as noted by fdb. On this work, see the blog post by Larry Hurtado, "NT Vocabulary in Historical Context". Hurtado also mentions the "New Documents Illustrating Early Christianity" series, and work in this sphere is not standing still. However, the venerable Moulton and Milligan is still valuable here.
Another step removed would get us to Philo (e.g. Q&A on Genesis, Q&A on Exodus, On the Contemplative Life; "Aristeas" (see appendix by Thackeray); then maybe Xenophon, and on and on. The exercise becomes less meaningful at that point, because there is a world of antique Greek literature -- and simply providing a list of names is not the point of this exercise.
Descriptive accounts of the Koine online
There are some valuable accounts of the language of the NT and its close literary companions. From current online offerings, see the Wikipedia entry, and also the "New Testament Greek Online" pages from the University of Texas, Austin.
Some of the older major grammars included a section situating the language historically, usually as part of the introductory material. Worth mentioning in particular are:
- F. Blass, Grammar of New Testament Greek (2nd English edition, 1905 [1911 printing]), esp. pp. 1-5;
- J.H. Moulton, A grammar of New Testament Greek, Volume 1 (T & T Clark, 1906), Chapter 2, "History of the Common Greek", pp. 22-41;
- A.T. Robertson, A grammar of the Greek New Testament in the light of historical research (Hodder & Stoughton, 1914), Chapter 3, "The Koine" (pp. 48-75) (and see the following chapter, too!).
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