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 did he rest his hope for forgiveness?
For what purpose did Christ come to this world?
What came out of one of the four horns of the goat?
How long did he continue this work there?
16. What striking testimony is borne by Neander, the noted church historian, regarding the origin of the Sunday Sabbath?
What was to he inflicted upon one of the heads of this beast?
How many will see Him when He comes?

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