I was sent the URL of an essay concerning Biblical leprosy (see Levit 13) written by the late and controversial scientist, Immanuel Velikovsky. The good doctor had suggested that the (alleged) prevalence of leprosy following the Jews' Exodus from Egypt could be explained by cataclysmic cosmic events that might have led to unusually high atmospheric radiation levels. The resultant contamination might have led to symptoms in humans similar to those described by the Bible as leprosy. I was then asked for my opinion.
(Those familiar with the Torah literature on the subject will, by the way, avoid translating "tzora'as" as leprosy. The problem - as so many of our commentators have pointed out - is that the "tzoras" described in the Bible bears precious little resemblance to the disease of leprosy).
While expressing great love and respect for it, Velikovsky, I began, seemed to believe the Bible to be an historical fraud...
...The Bible states clearly, for instance, that "...GOD sent the sea with a strong east wind..." (Ex 14; 21). In other words, that the splitting of the sea was an act of Divine intervention in history and nature. Velikovsky admits the possibility that the sea split, but denies its Divine connection. His beloved Bible might still contain some social, emotional and historical significance for modern man, but its central claim of Divine origin - upon which the objective authenticity of everything else rests - is, according to Velikovsky, false.
But I think he went much further than that: much of his life's work involved playing around with ancient chronology. While he seemed to consider the Bible's version the most complete and accurate source of evidence, it was, to him, nothing more than a source of evidence and he freely admitted the possibility of some margin of error. Again: if it was truly Divine, then there could be no errors at all (unless we heavily redefine our understanding of what God is).
Throughout his work (and very clearly in the article you've brought to my attention), Velikovsky works on the assumption that there was no God standing behind "miraculous" events, but rather that they were the result of massive accident or coincidence - in either case, perfectly explainable in rational terms (if you accept his science, that is).
As one observer I came across noted, Velikovsky allowed you to harbor some vague feelings of religious sentiment ("there's something to this book!") without being burdened by the full weight of its implications ("but there are no absolute and binding moral or social requirements that come from it"). Religion lite.
Now, with all of that as an introduction, I will offer my reaction to this particular article: Speculation is an exciting sport. One can speculate that the Jews leaving Egypt were leprous or that the tzora'as in the wilderness was radiation sickness even though there really isn't any hard evidence to support it. But this suggestion that there may have been a random cataclysmic event that might have been manifested in high doses of radiation and that these doses might have made a very specific and limited group of human beings ill - for a limited time of seven or sometimes fourteen days (after which the illness mysteriously disappeared - try selling that to Madame Curie) is a far cry from presenting real historical or documentary evidence. It's nothing more than a good old fashioned game of blind man's bluff. There is an infinite array of possible scenarios one could offer - many with their own creative and ingenious backgrounds, but who's to say this one is any more likely than any other? Science is about suggesting the most likely possible explanation for a given phenomenon; not any possibility.
And, by the way, what's so difficult about considering the possibility that a Biblical event, just the way it was described in the Bible itself, was historical (i.e., that tzora'as was a spiritual disease caused by God)? Is that less likely or more speculative?
Is there any evidence to the contrary? Let's take a short look at the text of the Bible itself to see how well Velikovsky's scenario fits:
"If the tzora'as spreads in the skin and covers all the potentially receptive skin (see commentary of Rabbi S.R. Hirsch), from his head until his feet as far as the eyes of the priest can see. And the priest looks and behold, if the tzora'as has covered all of his flesh he shall pronounce the affliction pure, he has turned all white: he is pure. And on the day that healthy flesh is seen, he will become impure..." (Levit. 13; 12-14).
Now how does this law make any sense in the treatment of serious radiation illness (or leprosy, for that matter)? Just when the illness (or infection) has reached its peak - covering the entire body of its victim - only then do we send him back into the camp and declare him "fit and pure"?! No matter how primitive you think my ancestors were, would they really make such a huge medical blunder...especially given the enormous fear Velikovsky feels they must have had for the disease!
So whatever Velikovsky is describing with this (admittedly cute) radiation explanation, it certainly isn't the Biblical account.