Al-Hajj · 22:28

28. So that they come to what will bring them benefit such as forgiveness of sins, attaining reward, unity of word, and so forth; and so that they remember Allah on the animals they slaughter in the known days, which are: the tenth of Dhu’l-Hijjah and three days after it, in gratitude to Allah for the camels, cows and sheep He granted them. So eat of these animals and feed from them those who are extremely poor.