The Bible speaks of two covenants of God with humanity, the first was a covenant full of laws and prohibitions, a pact that Paul defined as something that was almost impossible for man to be saved and that did not include all humanity, that Covenant was full of rites, cults and ordinances and for man all these things were very complicated. But in advance a second covenant had been promised, which would be better than the first, which would end once and for all with sin. Remember that through Adam’s sin death reigned, but the history did not stay in Eden, but God sent us to Christ and through Him came life.
The author of the book of the Hebrews begins speaking in chapter nine of the characteristics of the old covenant, of how the cult was, of how those sacrifices that were offered continuously were insufficient to end the sin, but later speaks of a sacrifice that ended once and for all with sin and with death, and is the sacrifice of our beloved Christ. The author says:
So Christ was sacrificed once to take away the sins of many; and he will appear a second time, not to bear sin, but to bring salvation to those who are waiting for him.
Hebrews 9:28
