The Torah in Numbers 29:12-34 requires the Israelite priests to sacrifice 70 bulls during the great feast of Sukkot-Asif. The question standing before most people who read this text is why 70?
In traditional interpretation found in rabbinic sources, we find the argument that 70 represents the 70 nations mentioned in Genesis 4. The concept revolves around the universality of YHWH in the mind of 2nd temple Judaism and the idea of the universal responsibility of Israel.