We would only need scientific explanations for Jesus' miracles if they were attested outside the gospels. Yet, in spite of the number of miracles he performed and the wonder and excitement they would have caused, there is not one contemporary, non-biblical account of even one miracle performed by a holy man in Palestine. It is as if they never happened.
Some of the miracles in the gospels can be explained by looking at the history of the gospels. We now know that the gospels were not written by eyewitnesses or even by anyone who knew an eyewitness. We know that
Mark was the first gospel written, around 70 CE, and that the Gospels of Matthew and Luke were substantially based on that of Mark. Finally, it can be shown that the Gospel of John was based on that of Luke, with some minor additions taken direct from
Mark.
Since the authors of
Matthew, Luke and
John clearly knew nothing of the life and misssion of Jesus apart from what came, directly or indirectly, from
Mark, it would be reasonable to conclude that any miracle reported in the other gospels, but not in
Mark, is not historically true. Thus, when
John talks of Jesus raising Lazarus, brother of Mary and Martha, from the dead, this can be seen as a conflation and elaboration of the two stories about Mary, Martha and Lazarus in
Luke, which gospel has Jesus talk in a parable about the hypothetical resurrection of Lazarus.
So, only the miracles in the Gospel of Mark need to be considered. The miracle of Jesus walking on water is so remarkably similar to the Homeric account of the god Hermes walking on water in similar circumstances that any attempted scientific explanation of one would apply equally to the other. The gospel episode is clumsily structured, clumsily inserted into the context, and its reason is hard to explain except as evidence to the readers of Jesus' supernatural powers. Dennis R. MacDonald concludes that this miracle account was actually based on Homer, as (according to MacDonald) were many others in Mark's Gospel.