George Salmon:
It seems to me also that the hand of the writer of the concluding verses is to be found elsewhere in the Gospel. Three times in these concluding verses attention is called to the surprising slowness of the disciples to believe the evidence offered them (vv. 11, 13, 14). Now, you will find that the thought is constantly present to the mind of the second Evangelist, how slow of heart were the beholders of our Lord's miracles; how stubborn the unbelief which the evidence of these miracles was obliged to conquer. Thus, in the account of the healing of the man with the withered hand (common to the three Synoptics), Mark alone relates (iii. 5) that before commanding the man to stretch forth his hand our Lord looked round on the bystanders 'with anger, being grieved for the hardness of their hearts.’ Again, in Mark vi. 6 there is a note special to this Evangelist: ‘Jesus marvelled because of their unbelief.’ And in the history of the tempest on the lake of Gennesaret, told both by Matthew and Mark, there is a noticeable difference between the two accounts. Where Matthew (xiv. 33) tells of the conviction effected by the miracle in those who beheld it, Mark (vi. 52) has instead an expression of surprise at the stupidity and hardness of heart of those who had not sooner recognized our Lord’s true character.
Believing, then, the existing conclusion to have been part of the Second Gospel, ever since it was a Gospel ...
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