How early was this sacrificial system known?

Answer

"By faith Abel offered unto God a more excellent sacrifice than Cain, by which he obtained witness that he
was righteous, God testifying of his gifts." Heb. 11: 4. See Gen. 4: 3-5; 8: 20.

From what is a converted sinner saved?
What part of the law of God especially has the Papacy thought to change?
6. What influence do the Bible and history show working in the church immediately after apostolic days?
What was Satan's design in thus persecuting the church?
Are the angels interested in the plan of salvation?
What is one good evidence of genuine repentance?
What will be excluded from this city?

Questions & Answers are from the book Bible Readings for the Home Circle