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.

What is the result of faith's being put to the test?
How earnestly should parents teach their children the things of God?
Through which covenant only is there remission f sins?
Does the Bible recognize this as the proper time for beginning and ending the Sabbath?
What becomes of the living wicked when Christ comes?
What was the burden of the message of John the Baptist?
Who will be permitted to enter it?

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