Without the Dead Sea Scrolls, "scholars" who despise Judaeo-Christianity would still be trying to persuade us that "the Old Testament was written late" and that "the prophecies which define the Messiah were add-ons". During the so-called Age of Reason, this is precisely what such people taught.
The discovery of the scrolls at Qumran - left behind by some kind of extreme Jewish or possibly Essene sect - meant such people were dead in the water. The dating was historically unarguable!
The scrolls represent every book of the OT except Esther and thus confirm that the countless prophecies which Jesus fulfilled all pre-dated Him.
Of course, the next step was to attack the veracity of the Gospels which is considerably more difficult. I shall leave that for another time.
LINK: http://mosaic.lk.net/g-qumran.html
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