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.

For what purpose were the Scriptures written?
In what psalm was the resurrection of Christ foretold?
What illustration of this is given in the Bible?
In what words will their triumph over death and the grave be expressed?
Is there danger of believers losing their hold on Christ?
What only can overcome the world?
What determines whether one is a child of Abraham?

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