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.

9. In what words to Peter did Jesus indicate the kind of service a converted person should render to his brethren?
What will he the reward of those who honor their parents?
To whom does God reveal the secrets of the future?
If one professes to abide in Christ, how ought he to walk?
Of what was this memorial to he a sign?
What was Christ's reply?
Whom did Christ indicate as fulfilling this prophecy?

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