Investigating the roots of western civilization (ye olde BC&H forum of IIDB lives on...)
https://earlywritings.com/forum/
I do not have a complete response prepared, but you may be interested in glancing over something I posted a while back about the Suffering Servant and the Dead Sea scrolls: viewtopic.php?f=6&t=5640.
Later, of course, Jewish exegetes interpreted the Servant as the Messiah. But it is naturally controversial how far back in time this interpretation goes.
Hymn 17:
For You, O my God, have concealed me from mankind, and Your law You have hidden in me until the time You reveal Your salvation in me. For in my soul's distress You did not abandon me, but You heard my cry in the bitterness of my soul.
Hymn 18:
And concerning the mystery which You hid in me, they go about as slanderers to the children of destruction. Because You have exalted yourself in me, and forsake their guilt, You have hidden in me the spring of understanding and the counsel of truth.
This text also shows us that the portrayal of this Messiah-priest with the features of the Suffering Servant of Deutero-Isaiah is not an innovation of purely Christian origin either, but the result of previous developments ... Whatever might be the possible allusion to the death of the expected Messiah-priest, the identification of this figure with the Servant of Isaiah seems confirmed by the parallels...
https://books.google.com/books?id=nmvkd ... on&f=false