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 are the wages of sin?
In what plain words did Christ foretell His resurrection?
Why should husbands be considerate of their wives?
By what means may the mother bind the hearts of the loved ones at home together?
When some went out to gather manna on the seventh day, what did the Lord say to Moses?
In what language is this clearly stated?
14. Besides telling His disciples when to flee, how did Christ further show His solicitude and tender care for them?

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