Why does the Torah insert the (otherwise superfluous) word "ha'Ganav"?
Sanhedrin, 72a: To teach us that the the same Din will apply even if the Ganav is found entering the house via the roof, the courtyard or via an enclosure, and the Torah only mentions a tunnel because it is the most common. 1
According to another Berasisa in Sanhedrin, Ibid., the Torah mentions a tunnel because the fact that he entered via a tunnel serves as his warning, and no other warning is required, as opposed to where he enters the roof, the courtyard or via an enclosure, where he must be warned before one may kill him. See Torah Temimah, note 5.
Why is one not Chayav for killing the Ganav whom he catches tunneling into his house?
Rashi (citing Rava in Sanhedrin, 73a) and Rashbam: Because it is obvious that the Ganav is desperate and that he will not hesitate to kill 1 anyone who catches him in the act 2 (because he comes ready to kill or to be killed - Rashbam).
Yoma, 85a (citing R. Yishmael): Because he has no value. 3
Since he knows that the owner will not stand idly by as he proceeds to rob him (Rashi). See also Ba'al ha'Turim.
Also because it is speaking about where he catches him at nighttime. (Rashbam).
Yoma (Ibid.): And if one is permitted to kill him even though it is not one hundred per cent sure that he will kill the owner if he is caught, and even though murder renders the land Tamei and causes the Shechinah to depart from Yisrael, how much more so does Piku'ach Nefesh override Shabbos! See Torah Temimah, note 1.
What are the implications of the words "ve'Hukah u'Meis ... "?
Sanhedrin, 72b: "Vehukah" implies that whoever finds him - even if it is not the owner - may kill him, and "u'Meis", that he may kill him in any possible way. 1
See Torah Temimah, note 7.
Why does the Torah not obligate whoever finds the Ganav tunneling, to kill him like it does a murderer (as Tosfos points out in Sanhedrin, Daf 73a)?
Oznayim la'Torah: Because it is not absolutely certain that he will kill the owner if he catches him. 1
See Oznayim la'Torah who discusses the difference between R'shus and Chiyuv and between the owner and anybody else who catches the Ba ba'Machteres.
What are the connotations of "Ein lo Damim"?
Rashi: It means that he is like someone who has no blood, and killing him is therefore not considered murder. 1
Rashbam: It means that he is exempt from paying [for what he steals 2 or breaks]. Rather, one who kills him is exempt. 3
Targum Yonasan: Whoever kills him is not guilty of shedding innocent blood.
Sanhedrin, 72b: Refer to 22:1:2:1. And one is permitted kill him even on Shabboa - even though Beis-Din are not permitted to carry out the death-sentence on Shabbos. 4
Rashi: Refer to 22:1:1:1 and note, This teaches us that if someone comes to kill you, beat him to the draw and kill him first!
Provided he breaks it. If however, it is still intact, he does not acquire it and is obligated to return it to the owner - See Oznayim la'Torah on Pasuk 2, DH 'Shalem Yeshalem' who elaborates at length.
Seemingly, these are two explanations. Perhaps he says 'rather', for they depend on each other. He is exempt from paying because one who kills him is exempt (Kam leih bi'de'Rabah Mineih - PF). Refer to 22:2:1:3. See also Oznayim la'Torah on Pasuk 2, DH 'Shalem Yeshalem'.
See Torah Temimah, mote 8.
Why does the Torah discuss specifically tunneling into a house?
Da'as Zekenim and Hadar Zekenim: Because only then is the Ganav ready to kill the Ba'al ha'Bayis (as opposed to a Ganav who enters through the door [or window], who intends to flee via the door [or window] if the Ba'al ha'Bayis catches him - Hadar Zekenim).
Sanhedrin, 72a #1: In fact, the same applies to a Ganav whom one finds on the roof or in one's courtyard or enclosure, 1 and the Torah mentions tunnel only because that is where one generally finds him. 2
Sanhedrin, 72a #2: Refer to 22:1:0.1:1*.
Yerushalmi Sanhedrin, 8:8: Because it is only in the tunnel that he 'has no value' and the owner is permitted to kill him, but not once he has left it and turned to flee. 3
