The fact that Mark begins his Gospel with the baptism scene has often been taken to indicate his espousal of adoptionist christology which excludes any attribution of intrinsic divinity. On the whole, this proves to be untenable. Mark specifically identifies John’s baptism as the beginning of the gospel, not of Jesus; there is no denial of Jesus’ personal preexistence, a necessary corollary of divinity. On the contrary, even though the ascription of sonship in 1.11 is phrased in terms of Ps. 2.7, the specifically adoptionist element of that verse is omitted. Instead of ‘this day I have begotten you’, we read, ’with you I am well pleased.' The aorist probably indicates that God’s pleasure in Jesus is already established and does not arise as a sudden whim; Mark began his Gospel with one of his rare biblical citations in order to show that the events he narrates are part of God’s longstanding plan (1.2-3). This leaves us with twological alternatives for the origin of God’s pleasure: Jesus’ preexistence; or his uniquely pleasing earthly life before his baptism.
Clearly, the former is to be preferred. If Jesus’ adoption at the baptism was the reward for his previous deportment, how could Mark refrain from describing that meritorious early life? More importantly, Mark’s divine-human dichotomy is too radical to allow for the implication which arises from adoptionism, which is that the gulf could be bridged from the human side (8.37f.). Finally, given the wide attestation of divine-human christology in Christian sources earlier than and contemporary with Mark, any espousal of adoptionism would need to be quite pointed; but this we do not find.
We do, however, find that Mark’s references to Jesus’ relationship to God lend themselves to the suggestion of intrinsic divinity. They issue largely from supernatural beings, either God (1.11; 9.7) or demons (1.24; 3.11; 5.7), implying that these are supernatural revelations about a supernatural person. Mark’s handling of the transfiguration as a whole raises Jesus above Elijah and Moses, emphasizing that he alone is the Son of God, to whom human beings must listen; he alone overcomes the dichotomy. Further, the parable of the vineyard (12.1-11) contains enough evidence of allegorization that the sending of the (already existing) beloved son in 12.6 is most plausibly understood as implying Jesus’ personal preexistence, much like Gal. 4.4.
Philip Davis, "Mark's Christological Paradox," JSNT 35, 1989, 3-18, 12-13.
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