The relationship Paul identifies in Galatians 3:13 between Christ’s crucifixion and Deuteronomy 21:22-23 is interesting because it is the one place in the typology argument where a mythicist might argue the New Testament crucifixion act itself is typology. That doesn’t help answering whether Paul started with memory of the historical Jesus being crucified and then shaped it according to Deuteronomy 21:22-23 in Galatians 3:13, or if Paul is indicating in Galatians 3:13 that he discovered that the celestial Jesus was crucified by an allegorical reading of Deuteronomy 21:22-23?
Strauss said: “when we find details in the life of Jesus evidently sketched after the pattern of these prophecies and prototypes, we cannot but suspect that they are rather mythical than historical. (Life of Jesus, Critically Examined, p. 89)”
Likely the clearest Prophecy about Jesus is the entire 53rd chapter of Isaiah. Isaiah 53:3-7 is especially unmistakable: “He was despised and rejected by men, a man of sorrows, and familiar with suffering. Like one from whom men hide their faces he was despised, and we esteemed him not. Surely he took up our infirmities and carried our sorrows, yet we considered him stricken by God, smitten by him, and afflicted. But he was pierced for our transgressions, he was crushed for our iniquities; the punishment that brought us peace was upon him, and by his wounds we are healed. We all, like sheep, have gone astray, each of us has turned to his own way; and the LORD has laid on him the iniquity of us all. He was oppressed and afflicted, yet he did not open his mouth; he was led like a lamb to the slaughter, and as a sheep before her shearers is silent, so he did not open his mouth.”
The only thing is, Isaiah wasn’t making a prophesy aboout Jesus. Mark was doing a haggadic midrash on Isaiah. So, Mark depicts Jesus as one who is despised and rejected, a man of sorrow acquainted with grief. He then describes Jesus as wounded for our transgressions, bruised for our iniquities. The Servant in Isaiah, like Jesus in Mark, is silent before his accusers. In Isaiah it says of the servant with his stripes we are healed, which Mark turned into the story of the scourging of Jesus. This is, in part, is where atonement theology comes from, but it would be silly to say II Isaiah was talking about atonement. The servant is numbered among the transgressors in Isaiah, so Jesus is crucified between two thieves. The Isaiah servant would make his grave with the rich, So Jesus is buried in the tomb of Joseph of Arimathea, a person of means.
Then, as Dr. Robert Price says
The substructure for the crucifixion in chapter 15 is, as all recognize, Psalm 22, from which derive all the major details, including the implicit piercing of hands and feet (Mark 24//Psalm 22:16b), the dividing of his garments and casting lots for them (Mark 15:24//Psalm 22:18), the “wagging heads” of the mockers (Mark 15:20//Psalm 22:7), and of course the cry of dereliction, “My God, my God, why have you forsaken me?” (Mark 15:34//Psalm 22:1). Matthew adds another quote, “He trusts in God. Let God deliver him now if he desires him” (Matthew 7:43//Psalm 22:8), as well as a strong allusion (“for he said, ‘I am the son of God’” 27:43b) to Wisdom of Solomon 2:12-20, which underlies the whole story anyway (Miller, p. 362), “Let us lie in wait for the righteous man because he is inconvenient to us and opposes our actions; he reproaches us for sins against the law and accuses us of sins against our training. He professes to have knowledge of God, and calls himself a child of the Lord. He became to us a reproof of our thoughts; the very sight of him is a burden to us because his manner of life is unlike that of others, and his ways are strange. We are considered by him as something base, and he avoids our ways as unclean; he calls the last end of the righteous happy, and boasts that God is his father. Let us see if his words are true, and let us test what will happen at the end of his life: for if the righteous man is God’s son he will help him and will deliver him from the hand of his adversaries. Let us test him with insult and torture that we may find out how gentle he is and make trial of his forbearance. Let us condemn him to a shameful death, for, according to what he says, he will be protected.”
As for other details, Crossan (p. 198) points out that the darkness at noon comes from Amos 8:9, while the vinegar and gall come from Psalm 69:21. It is remarkable that Mark does anything but call attention to the scriptural basis for the crucifixion account. There is nothing said of scripture being fulfilled here. It is all simply presented as the events of Jesus’ execution. It is we who must ferret out the real sources of the story. This is quite different, e.g., in John, where explicit scripture citations are given, e.g., for Jesus’ legs not being broken to hasten his death (John 19:36), either Exodus 12:10, Numbers 9:12, or Psalm 34:19-20 (Crossan, p. 168). Whence did Mark derive the tearing asunder of the Temple veil, from top to bottom (Mark 15:38)? Perhaps from the death of Hector in the Iliad (MacDonald, pp. 144-145). Hector dies forsaken by Zeus. The women of Troy watched from afar off (as the Galilean women do in Mark 15:40), and the whole of Troy mourned as if their city had already been destroyed “from top to bottom,” just as the ripping of the veil seems to be a portent of Jerusalem’s eventual doom.