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 prophecy are Christ's life, suffering, and death touchingly foretold?
What reason is given for Gods readiness to forgive sin?
After He had prayed this remarkable prayer three times, what occurred?
Whose presence does the Holy Spirit bring to the believers?
In what were the laws or commandments respecting sacrifices and burnt offerings written?
What takes place under the seventh plague?
For what purpose did Christ say God had anointed Him?

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