Ba Ba'Machteret: Standing your Ground in Halacha

אִם־בַּמַּחְתֶּ֛רֶת יִמָּצֵ֥א הַגַּנָּ֖ב וְהֻכָּ֣ה וָמֵ֑ת אֵ֥ין ל֖וֹ דָּמִֽים׃ אִם־זָרְחָ֥ה הַשֶּׁ֛מֶשׁ עָלָ֖יו דָּמִ֣ים ל֑וֹ ...׃

If the thief is seized while tunneling, and he is beaten to death, there is no bloodguilt in his case. If the sun has risen on him, there is bloodguilt in that case...

ת"ר (שמות כב, א) אין לו דמים אם זרחה השמש עליו וכי השמש עליו בלבד זרחה אלא אם ברור לך הדבר כשמש שאין לו שלום עמך הרגהו ואם לאו אל תהרגהו תניא אידך אם זרחה השמש עליו דמים לו וכי השמש עליו בלבד זרחה אלא אם ברור לך כשמש שיש לו שלום עמך אל תהרגהו ואם לאו הרגהו קשיא סתמא אסתמא לא קשיא כאן באב על הבן כאן בבן על האב
§ Apropos a burglar who breaks into a house, the Sages taught in a baraita: The verses state: “If a burglar is found breaking in, and is smitten and dies, there shall not be blood shed on his account. If the sun is risen upon him, there shall be blood shed on his account” (Exodus 22:1–2). A question may be raised: But did the sun rise only upon him? Rather, these words must be understood in a metaphoric sense: If the matter is as clear to you as the sun that the burglar is not coming to you in peace, but rather his intention is to kill you, arise and kill him first. But if you are not sure about his intentions, do not kill him. It is taught in another baraita: The verse states: “If the sun is risen upon him, there shall be blood shed on his account.” A question may be raised: But did the sun rise only upon him? Rather, these words must be understood as follows: If the matter is as clear to you as the sun that the burglar is coming to you in peace, do not kill him. But if you are not sure about his intentions, arise and kill him. The Gemara notes a difficulty: The halakha in the undetermined case as stated in the first baraita contradicts the halakha in the undetermined case as stated in the second baraita. The first baraita indicates that if the homeowner is unsure about the burglar’s intentions, he is prohibited from killing the burglar, whereas the second baraita indicates that in such a case, he is permitted to kill the burglar. The Gemara answers: This is not difficult. Here, where the baraita teaches that if one is unsure about the burglar’s intentions it is prohibited for him to kill him, it is referring to a father who comes to rob his son. A father has great compassion for his son, and therefore it may be presumed that he will not kill his son if he resists. Accordingly, the son is prohibited from killing his father unless he knows for certain that his father has the intention of killing him. There, where the baraita teaches that if one is unsure about the burglar’s intentions it is permitted for him to kill him, it is referring to a son who comes to rob his father. Since a son has less compassion for his father, it may be presumed that he would be ready to kill his father if he resists. Therefore, the father is permitted to kill his son unless he knows for certain that his son would never kill him.

What is the law regarding a case where one is not sure about the intruder's intentions?

אם במחתרת ימצא הגנב. כלומר אין המכהו נחשב כשופך דמים שהרי כמו אנוס הוא שאין אדם יכול להעמיד עצמו על ממונו וזה נחשב כמו רודף כמו שאמרו רבותינו דדעתו שאם יעמוד אדם נגדו שימיתנו ובא להרגך השכם להרגו:

אם זרחה השמש. שיצא מן המחתרת לאויר העולם מקום זריחת השמש:

דמים לו. ואם הרגו נחשב עליו כרוצח ושופך דם דלא הותר לו רק בשעת חימום במחתרת ומשום הכי חייב אם המיתו ואין לו עליו רק תשלומין:

if the thief is seized while tunneling: which is to say that the homeowner is not judged as a murderer, rather as someone in a forced situation, for we cannot expect a person to stand by as his possessions are taken. This is comparable to a case of a Rodeif where, according to our tradition, if a person is attacked by a potential killer that person may kill that attacker first.

If the sun has risen on him: That is to say that the thief has left the person's home and is now outside in the sunlight.

there is bloodguilt in that case: And if the homeowner kills the thief in that case he is judged as a murderer, being that the Torah only gave the homeowner permission while he was enraged at the thief being in his home. Therefore, the homeowner would be guilty if he kills the thief and the thief would only be responsible for paying for any stolen items.