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.

For what spiritual gift did the Apostle Paul pray?
How did the father show his joy at his son's return?
8. When did the Gentiles request that Paul should repeat the sermon he had preached at Antioch on the Sabbath?
What was the burden of the message of John the Baptist?
11. Should we allow ourselves to be influenced by signs or wonders performed by those who would try to lead us away from God and His law?
What will he one of the last great signs performed by this means, to fasten men in deception?
By what may we be partakers of the divine nature?

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