Ruben A. Būhner discusses the charge of "blasphemy" against Jesus in Mark 14; argues it is a result of Jesus claiming divinity for himself.
Ruben A. Būhner, Messianic High Christology: New Testament Variants of Second Temple Judaism (Waco, Tex.: Baylor University Press, 2021), 73-75
Beyond the expression “the son of man,” the epiphenomenon of Christ’s second coming, namely his “coming with the clouds of heaven,” is an allusion to Dan 7:13. More importantly, it bears some interesting superhuman connotations that once again resemble the messianic discourse of Second Temple Judaism. In light of similar passages from writings grouped together in the Hebrew Bible, the coming with clouds suggests a divine epiphany of no one else but the one God of Israel. Within the Hebrew Bible, it is mostly God himself whose coming or presence is accompanied by clouds: This applies for instance to the cloud during the Exodus (Exod 14:20), to Solomon’s dedication of the temple (1 Kgs 8:10f.), to prophetic oracles (Isa 19:1), and also to Ezekiel’s vision of God’s throne (Ezek 1:4). All in all, coming with clouds seems to be a standard repertoire of theophanies for the biblical literature. By using this expression, Mark 14:62 also presents Christ as a heavenly and divine being. Additionally, this presentation of Christ with epiphanic traits is an already known phenomenon for the reader of the Gospel (see Mark 4:35-41; 6:45-52; 9:2-10).
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Additionally, the high priest’s reply with the charge of blasphemy seems to fit the superhuman claims in Jesus’ answer. Although some scholars interpret the charge of blasphemy as referring only to Jesus’ claim of being the messiah, such an understanding is impossible for two reasons. First, at least on historical grounds, the claim of being a messiah would not have been any basis for a death sentence according to Jewish law. Second, and more important, such an understanding ignores the context within the whole Gospel of Mark, since in Mark 2:7 the charge of blasphemy is clearly connected to the claim of divinity and not just to messiahship. Therefore, also in Mark 14, it is most likely that the charge of blasphemy is indeed referring to Jesus’ claims of divinity (or, in the words of Evans: “In the eyes of the high priest and those who agreed with him, Jesus committed blasphemy when he claimed a heavenly identity. He claimed to be the ‘son of God’ in the highest sense, whereby he might even sit upon God’s throne itself’. Thus, not only Jesus’ answer but also the high priest’s reply with the charge of blasphemy against Jesus, and maybe even the high priest’s initial question, are consistent in portraying Jesus as a figure with superhuman characteristics or at least with claims to such.