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.

Unto whom will the saints forever ascribe praise?
In what prophecy was the work of reconciliation foretold?
What is revealed in the gospel?
What final call to come out of Babylon is to go forth?
How enduring is the moral law?
What does Malachi say of those that fear the Lord?
What fate awaits those who turn a deaf ear to the poor?

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