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 witness does the true believer in Christ have that he is accepted of God?
When Christ thus ministers the law in the heart, what does it become?
When some went out to gather manna on the seventh day, what did the Lord say to Moses?
Still bent on persecution, how does Satan manifest his enmity against the remnant church?
7. What, according to Matthew's account, did Christ say were to he the signs in the sun, moon, and stars?
To whom do those things which are revealed belong?
Through whom is this first dominion to be restored?

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