Hebrews 13:10 MSG

[10] The altar from which God gives us the gift of himself is not for exploitation by insiders who grab and loot. In the old system, the animals are killed and the bodies disposed of outside the camp. The blood is then brought inside to the altar as a sacrifice for sin. It’s the same with Jesus. He was crucified outside the city gates—that is where he poured out the sacrificial blood that was brought to God’s altar to cleanse his people.