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.

How does Jesus, through the Spirit, seek an entrance to every heart?
How has God revealed to us the hidden things of the kingdom?
What statement shows that sin was in the world before the law was given on Mount Sinai?
With what words did God admonish Cain?
Is Christ coming again?
What will then take place?
What courage and strength, therefore, should come to us even in the hour of affliction?

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