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.

After the Flood, what came in consequence of further apostasy from God?
Why have all been reckoned under sin?
What blessed experience follows upon the acceptance of Christ as our righteousness?
What is the very life of the Spirit?
What does God say the Sabbath will be to those who hallow it, or keep it holy?
3. Through what experience was the church to pass, and what was to develop in the church, before Christ's second coming?
How may the- lack of wisdom be supplied?

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