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.

At the beginning of His ministry, what example did Jesus set for the benefit of His followers?
Upon what basis is justification granted?
What, therefore, did God do?
What only does Christ recognize as proper ground for dissolving the marriage relationship?
What testimony did Christ bear concerning His relation to the law and the prophets?
How is the closing period of tribulation of the church during this time referred to?
Why does God wish us to trust in Jesus?

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