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 chapter in the Bible is devoted to faith?
What was the character of- their deeds?
How did the Israelites in the wilderness on the sixth day prepare for the Sabbath?
Would God have His people unite in these combinations?
For what purpose did Christ say He would come again?
Who are to share this fate?
Whom will they be like?

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