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 the Comforter to do when He came?
What does this angel say?
What was done with the blood of the offering?
What was to he inflicted upon one of the heads of this beast?
What has always been the result of religious legislation or a union of church a state ?
7. What description does Paul give of the sufferings endured by some of God's people in former ages?
To what Old Testament promise did Peter evidently refer?

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