But this opens up room for questioning other verses in the OT that are taken to be foretelling Jesus, I mean Deuteronomy 18:18 is quite widely used for proof from what I've seen-which admittedly isn't much-or no?
The key reason that people will speak of Deuteronomy 18:18 referring to Jesus is because Peter quotes from Deuteronomy 18:15 (Acts 3:33) when he speaking to the crowd of onlookers after healing a beggar on the steps of the temple. Peter claims it was foreshadowing Christ.
As to whether or not it opens up room for questioning other OT passages that Christian claim as foretelling Jesus, I don't think you need my take on Deuteronomy 18 to provide that. I think that all of the OT passages that speak of Christ need to be seriously questioned.
Some Christians treat OT prophecies like you hear people talk about Nostradamus. They look at the their present experience and then read it into the words from the past. The result is that they claim to see things now, that no one saw at the time. Is that legitimate or not? Well, each person is going to have to make their own mind up on that. Some of it, such as the Messiah being from Bethlehem, makes sense to me. Other items I think are just excited people grasping at every thing that comes along and trying to make it fit.
And then there are passages that I think need to be understood as having two levels of meaning. Take Psalm 22 for instance:
Psalm 22
1 My God, my God, why have you forsaken me?
Why are you so far from saving me,
so far from the words of my groaning?
2 O my God, I cry out by day, but you do not answer,
by night, and am not silent.
3 Yet you are enthroned as the Holy One;
you are the praise of Israel.
4 In you our fathers put their trust;
they trusted and you delivered them.
5 They cried to you and were saved;
in you they trusted and were not disappointed.
6 But I am a worm and not a man,
scorned by men and despised by the people.
7 All who see me mock me;
they hurl insults, shaking their heads:
8 "He trusts in the LORD;
let the LORD rescue him.
Let him deliver him,
since he delights in him."
9 Yet you brought me out of the womb;
you made me trust in you
even at my mother's breast.
10 From birth I was cast upon you;
from my mother's womb you have been my God.
11 Do not be far from me,
for trouble is near
and there is no one to help.
12 Many bulls surround me;
strong bulls of Bashan encircle me.
13 Roaring lions tearing their prey
open their mouths wide against me.
14 I am poured out like water,
and all my bones are out of joint.
My heart has turned to wax;
it has melted away within me.
15 My strength is dried up like a potsherd,
and my tongue sticks to the roof of my mouth;
you lay me in the dust of death.
16 Dogs have surrounded me;
a band of evil men has encircled me,
they have pierced my hands and my feet.
17 I can count all my bones;
people stare and gloat over me.
18 They divide my garments among them
and cast lots for my clothing.
19 But you, O LORD, be not far off;
O my Strength, come quickly to help me.
20 Deliver my life from the sword,
my precious life from the power of the dogs.
21 Rescue me from the mouth of the lions;
save me from the horns of the wild oxen.
22 I will declare your name to my brothers;
in the congregation I will praise you.
23 You who fear the LORD, praise him!
All you descendants of Jacob, honor him!
Revere him, all you descendants of Israel!
24 For he has not despised or disdained
the suffering of the afflicted one;
he has not hidden his face from him
but has listened to his cry for help.
25 From you comes the theme of my praise in the great assembly;
before those who fear you will I fulfill my vows.
26 The poor will eat and be satisfied;
they who seek the LORD will praise him—
may your hearts live forever!
27 All the ends of the earth
will remember and turn to the LORD,
and all the families of the nations
will bow down before him,
28 for dominion belongs to the LORD
and he rules over the nations.
29 All the rich of the earth will feast and worship;
all who go down to the dust will kneel before him—
those who cannot keep themselves alive.
30 Posterity will serve him;
future generations will be told about the Lord.
31 They will proclaim his righteousness
to a people yet unborn—
for he has done it.
Psalm 22 isn't usually listed as one of the prophecies regarding Jesus. And of course it was meant to have meaning in its own day. But, as I read it, I see in it the life of Jesus so very strongly. Indeed, I think it was for this very reason that Jesus himself turn to and quoted from it while he was on the cross. It wasn't the cry of abandonment that so many take it to be, but a claiming of the ultimate promises of God's faithfulness described in this psalm.
Other passages, like Isaiah 7:14 "Therefore the Lord himself will give you a sign: The virgin will be with child and will give birth to a son, and will call him Immanuel." were certainly prophecy, but not specifically understood as Messianic prophecies until people like Matthew would later co-opt them in declaring the Christian gospel.
This sort of dual fulfillment is what I see happening in Peter's re-interpretation of Deuteronomy 18 and applying what I think was certainly originally understood as applying to Joshua and then deciding to also claim that it pointed to Jesus. Such may not be how we understand prophecy to work today -- we like to have one-to-one correspondence with things. But for the Hebrew mindset, such methodologies in interpretation were commonplace.
So, as we read these passages 2000 years removed from Peter's time, I don't feel that I can question his interpretation. But, when I am looking for the answer in my own mind, being the linear western thinker that I am, I will see Joshua.
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