Every spring in the village of Esfanjan in the city of Osko, East Azerbaijan Province, a ritual is performed on the axis of the sacrifice of a cow, which includes important elements of Iranian beliefs and rituals. According to this ancient tradition, the people of this village bought the bull that had been considered for a long time and returned it to the village on Thursday morning, which is 36 days past spring, and received the people's vows from the doors of the houses. After drinking the water of the subterranean aqueduct to the cow, they take it to the shrine of Pir Sang, which is located at the top of a hill next to the abode, and turn it around. They then descend from the hill and lead the victim to the top of the altar hill on the other side of the village, where they slaughter a girl near what they believe to be a missing place so that the cow's blood can flow through a groove into the pit and rain down. The study of the article in both field and documentary forms includes the description of religion and religious analysis and its myths, according to which the demand for rain, the myth of the absence of a girl and the sacrifice of a cow are the three main aspects of this religion based on Iranian culture. After Nowruz, it is also comparable to the "Mediozerm Gah" or "Mian Bahar" of the Zoroastrians. This ritual is also an unparalleled example in the variety of ritual elements, and in addition to the main elements includes defecation, collecting vows, moving cows in the village, bleeding in the absence of the girl, using the victim's blood for infertility, dividing and cooking the victim's meat.