In your insights you suggest that  Rashi 46a DH Pasha bi'Yenukei: The words "Malkeh Osam u'Mesim " should be "Malkeh Osam Yoser Midai " (as it appears in Rashi to Gitin 36a and to Makos 17a).
I learned this gemarah this week and was very troubled by it. I agree - i wish i would have seen Rashi in Bechoros choose the same words as he did in Gitten and Makos. However - he didnt.
Do you have any background information or other proof that this change should be made?
Please respond - i am really having difficulty with this Rashi.
Steven Zelcer, Brooklyn,NY USA
The Tzitz Eliezer (22:59) was asked this question and agrees that it is a strong question. However, I believe he has a nice answer as well.
First of all, he says, it is very clear that this very possibly only happened to a small amount of children (perhaps no more than two), and only happened after awhile because the teacher did not notice how frail they were, and that this would eventually cause their death. [He probably did not beat them on the spot until they died.]
However, most importantly, the only reason that he was taken back was because it was clear that he had changed his ways and would never do so again. When the Gemara says that Ravina took him back because he was so good, it meant that this was despite the Neder of Rav Acha, not despite the fact that he would kill the kids.
[I would add to his original statement that one never fully knows the physical state of another person. It is very possible that he would not intend to deliver a blow that would eventually kill the child, and he perhaps hit a child with a heart condition or one whose bones were fickle and this lead to their death. While this is not justification, and he still needed to do Teshuvah, it makes the case more understandable.]
All the best,