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 chapter in the Bible is devoted to faith?
What is the ultimate purpose of faith?
Does God design that His great work of creating the heavens and the earth shall be remembered?
When was the papal head of the first beast of Revelation 13 wounded?
What part will the angels have in this event?
8. After commending this church for their good works, what charge did the Lord bring against them?
What is said of charity in the Scriptures?

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