The Torah commands in Parashat Kedoshim (Vayikra 19:17), “Lo Tisna Et Ahicha Bi’lbabecha” – “Do not despise your fellow in your heart.” This refers specifically to a situation where one harbors hostility toward his fellow, but he keeps his hostility concealed, acting towards the person as though he likes him. The Torah demands that if we have some claim against our fellow, we should approach him and seek to resolve it, rather than keeping the hatred hidden within us. An example of this command is the Torah’s description of Yosef’s brothers’ feelings of animosity toward him: “They despised him, and they were unable to speak to him peacefully” (Bereshit 37:4). The Midrash comments that although the brothers were wrong for their hostile attitude toward Yosef, they are to be commended for not pretending to like him. They did not speak to him in a friendly manner as though they loved him, but rather made they feelings clear. The Sefer Ha’hinuch explained that the Torah forbids hating a fellow Jew because strife and divisiveness is “the lowliest and the absolutely most despicable quality.” Besides being inherently repugnant, hatred of other people leads to serious crimes such as physical violence and Mesira (informing about one’s fellow to hostile government authorities). This command, quite obviously, applies in all times, in all places, and to both men and women. Someone who despises a fellow Jew in his heart, without seeking reconciliation, transgresses this prohibition, but is not liable to Malkut, as Malkut are administered only for violations committed through a concrete action. The Sefer Ha’hinuch notes that the Torah forbids despising “your brother,” which implies that this prohibition applies only to “Ahicha Be’misvit” – a fellow Jew who is our “brother” with respect to Misva observance. As such, there is no prohibition against despising a Rasha (evil person). For the purposes of this command, a “Rasha” is defined as somebody who has transgressed the Torah on multiple occasions after being warned, openly defying the warnings. As this individual completely disregards the Torah, the prohibition of “Lo Tisna Et Ahicha Bi’lbabecha” does not apply. The Gemara in Masechet Yoma (9) famously teaches that G-d destroyed the second Bet Ha’mikdash on account of the sin of Sin’at Hinam (baseless hatred), because of the fighting among the Jews at the time. The first Bet Ha’mikdash, by contrast, was destroyed because of the people’s violation of the three cardinal sins of idol-worship, illicit relationships, and murder. Rabbenu Bahya (Spain, 1255-1340), in his Kad He’kemah, explains that the Gemara does not mean that Sin’at Hinam is equivalent to the combination of the sins of idolatry, illicit relations and murder. Rather, he writes, the Shechina (divine presence) cannot reside among us when we are divided and plagued by discord. G-d is one, and He thus can reside only among single, unified entities. When there is unity among Am Yisrael, and we are one people, G-d can reside among us; but when we break into different groups that quarrel with one another, the one G-d cannot reside among us, because we are then not a single entity. And once the Shechina departs, we are left without G-d’s protection, and thus vulnerable to our hostile enemies. Therefore, Jerusalem was destroyed as a result of the people’s Sin’at Hinam, which left the Jews without Hashem’s protection against the Roman Empire. It emerges, then, that “Lo Tisna Et Ahicha” is not only a Biblical command which we are obliged to obey, but also advice for our own benefit. We must avoid hatred and friction among Jews to obey this Misva, and, secondly, for our own protection, so that the Shechina will reside among us and protect us from harm.