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.

Upon what ground does God's work for sinners rest?
How many are sinners?
How is the righteousness thus obtained described?
How was the opening of the judgment to be made known to the world?
4. What was another memorial instituted to commemorate another signal providence in behalf of the Israelites?
What besides creation were Israel to remember when they kept the Sabbath?
Who is responsible for the present state Sunday laws of the United States?

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