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 remarkable experience attended the baptism of Jesus?
What was the special message for Noah's day?
How futile was all this?
Who was represented by \"the great horn,\" and what followed when it was broken?
How did Jesus answer them?
Which commandment alone of the Decalogue reveals the true God and Author of the law?
For what must men give account in the judgment?

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