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 other way is this same truth stated?
What change is thus brought about?
7. How did the chief priests and Pharisees seek to prevent the fulfilment of Christ's words concerning His resurrection?
When did this long period expire?
What may be known with equal certainty when these signs have been seen?
What is promised those who add grace to grace?
What only can overcome the world?

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