That’s worse than strange. Hitting for no reason is only okay when training for some purpose, not just as a hobby. Because it causes damage and it’s very dangerous. Especially in the case mentioned, we saw damage to clothing. In another case the damage could be much worse—think what would have happened if the nail had gone into his body and stabbed one of his friend’s internal organs?

In my opinion you are obligated to pay him for all the damage, because you are on equal terms*. According to the Torah, you need to take the shirt from him and buy him another one just like it.

* Equal terms — according to the Torah, if he had broken your arm, then you would have needed to receive from him its full value and also compensation for your lost time. So too regarding damage to property.

There is no such thing as hitting by consent—because the other person can always exploit that opportunity for the worse. And the Sages said: anyone who raises his hand against his fellow is called wicked.

Kahet, it’s time for you to grow up.

Moshe,
You write in such a decisive way as if you were the Oracle of Delphi, without knowing at all what you’re talking about. I’ve already commented to you about this in the past.

Sotah 22a:
“What is a minor whose months were not completed? Here they explained: this is a Torah scholar who kicks against his teachers. Rabbi Abba said: this is a student who has not yet reached the level to issue rulings and yet does so. For Rabbi Abbahu said that Rav Huna said that Rav said: What is the meaning of the verse, ‘For she has cast down many wounded, and all her slain are mighty’? ‘For she has cast down many wounded’—this is a Torah scholar who has not yet reached the level to issue rulings and yet does so; ‘and all her slain are mighty’—this is a Torah scholar who has reached the level to issue rulings but does not do so.”

Of course you can express an opinion even without being an expert, but the decisiveness—as though there were a ruling here from the mouth of the Almighty—is problematic when it comes against a background of lack of halakhic knowledge.
To remove any doubt, there is definitely room to discuss what I wrote above (I also hesitated a bit, because this is not a simple point of Jewish law. The question is what the relation is between this and “tear my garment”). But I thought about it and came to the conclusion that in my opinion he is exempt in a case like this.

There is no doubt, honored Rabbi, that you are right. The difference between us is small. I put up a fence so that both of them would understand for the future that if they fight and some damage happens, the other one has to pay. Neither I, nor you, nor the Torah wants people to fight—even not as a joke and not casually.

I repeat and say: in strange and severe cases like these, you need to relate to it accordingly and strictly. You have to think of it as if they were our children.

We’re in a discussion—why do I have to agree with everyone? In fact, honored Rabbi, you also said your opinion and it’s very acceptable to me. I also presented my opinion, and I wasn’t afraid because I care about the truth. And why should I hide my opinion even if I’m considered immature? I’m sure that that boy and anyone else does not rely on my decisive opinions!
And if I teach, I still do not issue halakhic rulings—and I am not a rabbi and not wise and expert like you, certainly. But I enjoy engaging in Torah and sharpening my thinking as much as possible.

Precisely someone whose months were not completed and who has something to say—that indicates that his brain is working. According to what is brought in Sotah, the Rabbi defines me as a Torah scholar—that’s already good enough for me. As they say, Rabbi, I nurse on the words of those greater than me—and please judge me favorably. And therefore, my father are you.

Moshe, “you put up a fence for them”? That really has nothing to do anymore with presenting your opinion. Did they appoint you to be their arbitrator and explain that from now on they’ll have to pay? So what if the Torah doesn’t like quarrels? “You have to think of it as if they were our children”?!?!

Of course, Jewish law needs to include everything. I already hinted at it, and make a kal va-chomer: if a person who raises his hand against his fellow is called wicked, then all the more so someone who actually hits him is wicked. And if he is wicked, then that is already a sin. So how can I exempt him? What do you want—that I should stand by and encourage them to fight? Certainly our children… all the children of Israel are brothers… each one is responsible for the other, and not an Arab to the other. That is my opinion—you have the right not to agree with it—I respect that.