BDAG Bibliography Expansion: Biblical Studies (25 vols.) includes twenty-five classic works of Biblical research that the editors of the standard Greek-English lexicon for the New Testament considered important for Greek lexicography. The third edition of A Greek–English Lexicon of the New Testament and Other Early Christian Literature, when it was published nearly 20 years ago, represented a watershed moment for New Testament studies. The most well-known change was Danker's inclusion of extended definitions But sometimes elements of the lexicon that did not change in the 3rd edition are as important as those that did. BDAG is also famous (and some would say “infamous”!) for the vast quantity of its citation of secondary literature. Frederick Danker, himself, believed that these citations of the secondary literature were essential for students and scholars alike.