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 contrast is drawn in the Scriptures between the Creator and false gods?
What is said of the strength and wisdom of God?
What did the Apostle Peter associate with baptism in his instruction on the day of Pentecost?
After His resurrection, what effect had this prediction upon His disciples?
Following the signs of His coming, what did Christ say would take place?
For what purpose was the Revelation given?
What promise has God made to bereaved mothers?

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