In the last Mishnah, we spoke about being judged because of one's end—what one is going to do—even though one has not done it yet. Therefore, we kill to hold him back and prevent him from committing all crimes in the future.
Here we're going to talk about a different type of person who is going to be judged on account of what he may do. We'll talk about a thief who is tunneling into a house. He's digging a tunnel under a house to get in, and we say that the owner of that house is allowed to kill him.
The Mishnah says, “A burglar who digs a tunnel under a house in order to go steal from it is judged on account of his end, of what he's going to do.” You're allowed to kill that type of thief who's tunneling into a house in order to prevent him from killing the owner.
The thief here, if he's digging a tunnel into a house, knows that he may eventually encounter the owner, and if the owner resists, he's going to have to kill him. So we see that the thief here is ready to kill the owner of the house. If he does so, we're allowed to kill him because we're left with no other choice. The owner of the house is allowed to protect his own life, so he could assume that the thief is trying to kill him. Therefore, the thief has sort of like a din rodef (law of a pursuer). The thief is like a pursuer, and therefore the owner of the house is allowed to kill him.
If we're calling this burglar a rodef, then we sort of understand that he is liable to be put to death unless he leaves the house or clearly indicates that he's not going to kill the owner. He has a death sentence on him, and there's a halachic term called kim lei bid'rabba minei: the thief receives the greater punishment of two things.
So if somebody would have the death penalty on them, they'd be obligated to be put to death, and there's also a monetary obligation on them. Let's say they stole. They have to pay back Kefel, double. Then the thief would be exempt from the monetary obligation. So we'll apply that rule to this case of the burglar who is digging under a house.
If a burglar was entering the house through a tunnel and broke a barrel while breaking in, Halacha (Jewish law) is as follows: If he has blood—if he deserves to live and you weren't allowed to kill him—then the thief is obligated to pay for the barrel.
If it's clear that the burglar did not want to kill the owner, you're not allowed to kill the burglar in the first place, because the owner's life here is not considered to be in danger. Let's say, for example, a father breaks into a son's house. So we make the assumption that the father is not going to kill him. He's not going to kill the son. Maybe he's down on his luck. He's somebody who would do something so egregious as steal from his son, but he's never going to go to the point of killing him.
So if the son kills the father, he would be Chayav—he'd be obligated—because we can't make the assumption that the thief here was trying to kill the homeowner, because it's a father-son relationship. Therefore, there's no murder that could happen. You can't kill that thief.
So if the thief broke a barrel, then Chayav—he's obligated—because we don't have that principle that only the greater punishment stays, because there's no death sentence over here. But if he does not have blood, which means the thief deserves to die and killing him is allowed, as in a regular case of a burglar, then the thief would be exempt from paying because he is liable to the death penalty.
In this second case, killing the thief would be permitted. Therefore, we view him as somebody who's liable to the death penalty. If he's liable to the death penalty, any monetary obligation that he has that kicks in at the same time, he would be patur from—he would be exempt from—so he wouldn't have to pay for the barrel that he broke.
In the first case, you weren't allowed to kill him because we say that there was no possibility that the thief was going to come kill the owner of the house. Therefore, there's no death penalty over there, and the monetary obligation kicks in. So you would have to pay for that barrel.