Old test scripture testifying to the saving death of Christ, His Blood for them He died for, or shed it for. Christs blood shed was in regard to a covenant death Matt 26:28
28 For this is my blood of the new testament, which is shed for many for the remission of sins.
Now lets look at OT Zech 9:11
As for thee also, by the blood of thy covenant I have sent forth thy prisoners out of the pit wherein is no water.
That this is speaking also about Christ we appeal to Vs 9
9 Rejoice greatly, O daughter of Zion; shout, O daughter of Jerusalem: behold, thy King cometh unto thee: he is just, and having salvation; lowly, and riding upon an ass, and upon a colt the foal of an ass.
Which corresponds to Christ here Jn 12:12-15
12 On the next day much people that were come to the feast, when they heard that Jesus was coming to Jerusalem,
13 Took branches of palm trees, and went forth to meet him, and cried, Hosanna: Blessed is the King of Israel that cometh in the name of the Lord.
14 And Jesus, when he had found a young ass, sat thereon; as it is written,
15 Fear not, daughter of Sion: behold, thy King cometh, sitting on an ass's colt.
Christs Covenant Blood brings Salvation with remission of sins !