Almost every religion you have ever heard of was probably based on or is still a religion that practices the ritual sacrifice/murder of a living thing for some god. (Aka violence for holy purposes)

All over the world religions have abounded which demand Lambs or birds or even the hearts of one’s fellow humans to worship/sate/bribe gods.

Violence is not objectively “unholy” because “holiness” itself is subjective to the culture in which the acts are practiced.