I'm just commenting on the book of Tobit.
[quote="patrick457, post:3, topic:328722"]
That's because the Vulgate Tobit is an on-the-spot paraphrase made by St. Jerome from a Hebrew translation of an Aramaic version. (Jerome found a version of Tobit in Aramaic, or "Chaldean" as he calls it, but he wasn't very good at the language, so he had someone read and translate it in Hebrew for him.)
The NAB Tobit meanwhile is primarily based on one of two Greek texts, the longer one known as Greek II or GII. (The shorter version, or Greek I, is the basis for the RSV Tobit.) The Hebrew and Aramaic manuscripts of Tobit found in Qumran are close to GII, as well as to Latin translations made before Jerome (aka Vetus Latina), which is even closer to these texts, which is why most scholars today favor it. Before the discovery of the Dead Sea Scrolls, however, translators used GI, because it is the version found in most Greek manuscripts. (GII in its fullest form is found only in Codex Sinaiticus, and even it has a couple of huge lacunae or missing text.)
There you have it: at least three or four different versions of a single book! :p I recommend you read this thread I built up a while ago.
P.S. Note that Haydock's commentary was written before the Dead Sea Scrolls were found; when it speaks of the "Hebrew" it refers to late, medieval versions of Tobit in that language (there are four of them) - which was the only thing available to scholars at that time. (The number of versions just increased further! :D)
[quote="patrick457, post:15, topic:328722"]
There are five manuscripts of Tobit (4Q196-200), dating from the period between 100 BC to AD 25, found in Cave 4 in Qumran in 1952, but it was not until 1956 that the first report on the finds was published. The late J.T. Milik reported about the discovery of what was then fragments three manuscripts of Tobit in the report. More fragments were eventually found (which was also announced by Milik) until five texts were found in total. However, while Milik worked on piecing the fragments from a period spanning from 1953 to 1960, he never got around to actually publishing them (one of the main criticisms levelled against him, in fact, is how he contributed to the long delay of getting the Dead Sea Scrolls into public view by not completing all the work on his portion - and quite an amount of the discovered fragments were under his lot). It was Fr. Joseph Fitzmyer who would complete the work and publish them in 1995 (Discoveries in the Judaean Desert, volume 19).
All in all, these manuscripts (four in Aramaic, one in Hebrew) generally agree with the text of GII, but sometimes they also exhibit agreement with GI. (For example, in Tobit 14:2, 4Q196 (Aramaic) and 4Q200 (Hebrew) both agree with GI in stating that Tobit was fifty-eight when he became blind, as opposed to GII's sixty-two.) In some instances, the text provided could be shorter or longer, or at times agree more with the Vetus Latina versions over against GII. All in all, there are sixty-nine fragments or groups of fragments in these five texts: out of these sixty-nine, thirty-four tiny fragments are unidentified, giving us thirty-five identified fragments in total.
4QTob[sup]a[/sup] ar (4Q196, Aramaic, ca. 50-25 BC)
Fragments 1 (Tobit 1:17), 2 (1:19-2:2), 3 (2:3), 4 (2:10-11), 5 (3:5), 6 (3:9-15), 7 (3:17), 8 (4:2), 9 (4:5), 10 (4:7), 11 (4:21-5:1), 12 (5:9), 13 (6:6-8), 14 i (6:13-18), 14 ii (6:18-7:6), 15 (7:13), 16 (12:1), 17 i (12:18-13:6), 17 ii (13:6-12), 18 (13:12-14:3), 19 (14:7), 20-49 (??)
4QTob[sup]b[/sup] ar (4Q197, Aramaic, ca. 25 BC-AD 25)
Fragments 1 (Tobit 3:6-8), 2 (4:21-5:1), 3 (5:12-14), 4 i (5:19-6:12), 4 ii (6:12-18), 4 iii (6:18-7:10), 5 (8:17-9:4), 6-7 (??)
4QTob[sup]c[/sup] ar (4Q198, Aramaic, ca. 50 BC)
Fragments 1 (Tobit 14:2-6), 2 (14:10)
4QTob[sup]d[/sup] ar (4Q199, Aramaic, ca. 100 BC)
Fragments 1 (Tobit 7:11), 2 (14:10)
4QTob[sup]e[/sup] (4Q200, Hebrew, ca. 30 BC-AD 20)
Fragments 1 i (Tobit 3:6), 1 ii (3:10-11), 2 (4:3-9), 3 (5:2), 4 (10:7-9), 5 (11:10-14), 6 (12:20-13:4), 7 i (13:13-14), 7 ii (13:18-14:2), 8 (?), 9 (3:3-4?)
These fragments also exhibit some degree of minor variance with each other, which shows us that there was not really a fixed text of Tobit during the 1st century BC or the 1st century AD.