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 was one direct purpose of the incarnation of Christ?
What similar instruction was given to Titus?
What is said of the fourth kingdom?
How is the character of the law described by the Apostle Paul?
What day is especially indicated as the day to prepare for the Sabbath?
What part will the angels have in this event?
What did Paul say regarding our duty to the poor?

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