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 did Christ come into the world?
In what prophecy did Christ recognize Daniel as a prophet?
What assurance has God given of the judgment?
What petition was made to the emperor by a church convention of bishops in AD 401?
What promise is made to those who look for Him?
What were the colour and character of the fourth symbol?
6. Under the theocracy of Israel, what was the law concerning witches' and those who had familiar spirits?

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