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.

In what scripture does Christ apply the same emblem to Himself ?
What relationship to God is established by faith?
What kind of friend is He?
What special reason did the Israelites have for keeping the Sabbath?
For how long a time was the seventh-day Sabbath observed in the Christian church?
What is the chief occupation of Satan and his angels?
What does Paul say God has prepared for His people?

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