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.

By what means is sin made known?
In what way was Jonah a type of Christ?
How complete a Saviour is He?
With what promise do the Old Testament Scriptures close?
What power was represented by the ram having two horns?
How is their watch-care over God's people expressed?
What divine law of retroaction attends giving?

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