613 Mitzvot
Negative Mitzvah 302
Not to hate others

Lo-tisna et-achicha bilvavecha hoche'ach tochiach et-amitecha velo-tisa alav chet.
You shall not hate your brother in your heart. You shall surely rebuke your neighbor, and not bear sin because of him.

1 Yochanan/John 3:15
Everyone who hates his brother is a murderer, and you know that no murderer has eternal life in him.

This mitzvah is related to the sixth of the aseret hadibrot (10 sayings): "You shall not murder,"

Matthew 5:21-24
"You have heard that our fathers were told, ‘Do not murder,’and that anyone who commits murder will be subject to judgment. Moreover, I tell you that anyone who nurses anger against his brother will be subject to judgment; that whoever calls his brother, ‘You good-for-nothing!’ will be brought before the Sanhedrin; that whoever says, ‘Fool!’ incurs the penalty of burning in the fire of Gey-Hinnom! So if you are offering your gift at the Temple altar and you remember there that your brother has something against you, leave your gift where it is by the altar, and go, make shalom with your brother. Then come back and offer your gift.

Hatred and anger affects our relationship with YHVH.

Yom-Kippur [the Day of Atonement] atones for a person’s transgressions against God, but it does not atone for his transgressions against his fellow-man until he appeases him. (Mishneh Yoma 8:9)

Below are examples of how hatred and murder are connected:

Avshalom spoke to Amnon neither good nor bad; for Avshalom hated Amnon, because he had forced his sister Tamar. It happened after two full years, that Avshalom had sheepshearers in Ba‘al-Chatzor, which is beside Efrayim: and Avshalom invited all the king’s sons. Avshalom came to the king, and said, See now, your servant has sheepshearers; let the king, I pray you, and his servants go with your servant. The king said to Avshalom, No, my son, let us not all go, lest we be burdensome to you. He pressed him: however he would not go, but blessed him. Then said Avshalom, If not, please let my brother Amnon go with us. The king said to him, Why should he go with you? But Avshalom pressed him, and he let Amnon and all the king’s sons go with him. Avshalom commanded his servants, saying, Mark you now, when Amnon’s heart is merry with wine; and when I tell you, Smite Amnon, then kill him; don’t be afraid; haven’t I commanded you? be courageous, and be valiant. (2 Sh'mu'el/Samuel 13:22-28 HNV)

Esav hated Ya ‘akov because of the blessing with which his father blessed him. Esav said in his heart, "The days of mourning for my father are at hand. Then I will kill my brother Ya ‘akov. (Bereshit/Genesis 27:41)

You shall not go up and down as a slanderer among your people; neither shall you stand against the life of your neighbor. I am the LORD. ‘You shall not hate your brother in your heart. You shall surely rebuke your neighbor, and not bear sin because of him. You shall not take vengeance, nor bear any grudge against the children of your people; but you shall love your neighbor as yourself. I am the LORD. (Vayikra/Leviticus 19:16-18)

This verse talks about the ways hatred manifests itself:

These will be discussed more in other mitzvot soon.

For a practical understanding of this, suppose you have a neighbor who continually plays loud music - particular of a style you do not like. It would be neither appropriate to just fight with him or give him the silent treatment.

Rambam had the following to say on this subject: "If a person is wronged by another, he should not hate him and remain silent, as is said in regard to the wicked, "Avshalom spoke to Amnon neither good nor bad; for Avshalom hated Amnon" (2 Sh'muel/Samuel 13:22). Rather, it is a mitzvah for him to make this known to him, and say to him, "Why did you do this-and-this to me? Why did you offend me in this way?", as it is written: "Rebuke, rebuke your fellow." And if that person expresses regret and asks him for forgiveness, he should forgive him... This is what the Torah instructs us to do in the command of 'You shall not hate your brother in your heart; you must surely rebuke your neighbor'. (Vayikra 19:17)." (Mishneh Torah, Hilchot Dayot 6:6)

The purpose of such confrontation is to give the other fellow an opportunity to explain himself. He may be completely unaware that his smoke or his noise is actually reaching and disturbing you. In the worst case scenario that he was truly inconsiderate your rebuke may well elicit from him an apology for his behavior.
This is not merely good advice for neighbors. Many of the strained relations between husband and wife, parents and children and business associates could be averted if the injured party summoned up the courage to confront rather than let silence prolong the hatred. (Ohr Somayach, Ethics, The Silent (Mis)treatment, on website).

Shalom v'brakhot v'simcha,
Moreh Chizkiyah Shlomo (Carl Diers)