(1) The LORD spoke to Moses, saying: (2) Speak to Aaron and his sons and to all the Israelite people and say to them: This is what the LORD has commanded: (3) if anyone of the house of Israel slaughters an ox or sheep or goat in the camp, or does so outside the camp, (4) and does not bring it to the entrance of the Tent of Meeting to present it as an offering to the LORD, before the LORD’s Tabernacle, bloodguilt shall be imputed to that man: he has shed blood; that man shall be cut off from among his people.
With regard to bloodshed it is written: “Moreover, Manasseh shed innocent blood very much, until he had filled Jerusalem from one end to another” (II Kings 21:16). However, considering that the people during the Second Temple period were engaged in Torah study, observance of mitzvot, and acts of kindness, and that they did not perform the sinful acts that were performed in the First Temple, why was the Second Temple destroyed? It was destroyed due to the fact that there was wanton hatred during that period. This comes to teach you that the sin of wanton hatred is equivalent to the three severe transgressions: Idol worship, forbidden sexual relations and bloodshed.
תניא רבי אליעזר אומר כל מי שאין עוסק בפריה ורביה כאילו שופך דמים שנאמר (בראשית ט, ו) שופך דם האדם באדם דמו ישפך וכתיב בתריה ואתם פרו ורבו
It is taught in a baraita that Rabbi Eliezer says: Anyone who does not engage in the mitzva to be fruitful and multiply is considered as though he sheds blood, as it is stated: “Whoever sheds the blood of man, by man shall his blood be shed” (Genesis 9:6), and it is written immediately afterward: “And you, be fruitful and multiply” (Genesis 9:7).
תני תנא קמיה דרב נחמן בר יצחק כל המלבין פני חבירו ברבים כאילו שופך דמים א"ל שפיר קא אמרת דחזינא ליה דאזיל סומקא ואתי חוורא
The Gemara relates that the tanna who recited mishnayot and baraitot in the study hall taught a baraita before Rav Naḥman bar Yitzḥak: Anyone who humiliates another in public, it is as though he were spilling blood. Rav Naḥman bar Yitzḥak said to him: You have spoken well, as we see that after the humiliated person blushes, the red leaves his face and pallor comes in its place, which is tantamount to spilling his blood.
MISHNA: A burglar who is found breaking into a house may be killed by the owner of the house with impunity (see Exodus 22:1). He too is sentenced on account of his ultimate end, as it is presumed that if the owner of the house would resist the burglar, the burglar would kill the owner of the house.
מתני׳ ואלו הן שמצילין אותן בנפשן הרודף אחר חבירו להרגו ואחר הזכר ואחר הנערה המאורסה ...
MISHNA: And these are the ones who are saved from transgressing even at the cost of their lives; that is to say, these people may be killed so that they do not perform a transgression: One who pursues another to kill him, or pursues a male to sodomize him, or pursues a betrothed young woman to rape her.