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 precedes the manifestation of sin ?
What question did -Christ's wonderful teaching call forth?
What importance is attached to Christ's resurrection?
What is the fear of the Lord declared to be?
At Corinth what did he do on the Sabbath days?
When did David say he would be satisfied?
What will be the difference between the portion of the righteous and the wicked?

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