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.

By what name is Christ appropriately called?
Against what are husbands cautioned?
To whom does God reveal the secrets of the future?
How do those with renewed hearts and minds regard the commandments of God?
In His first recorded discourse, what did Christ say of the law?
What is to be finished when the seventh trumpet is about to sound?
How will the ransomed of the Lord return to Zion?

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