______________________________________________________The curse is that man has to labor to get food from the ground. Cain gave an offering from the ground, but did not get blessed. Now if we look through scripture, are there other people that gave offerings from the ground. Yes. Did they get blessed? Yes. So if Cain gave from ground, and did not get blessed, yet other people have gave from the ground and did get blessed, that would show us that the ground was not the issue. But when we look at that passage what did Abel do, that it does not say Cain did? Give his first fruit. Now since there is so many scriptures that talk about a relationship between first fruit, and blessings, I would think we have to assume this was the reason Cain did not receive blessing.
There it is: the "man has to labor" to eat. The ground was not cursed to bear no fruit: it was cursed to make getting the fruit more difficult. But the blessing in man overcomes the curse of the ground!
But I also think that Abel believed the testimony of his parents: and that is where faith comes in. It is in giving to God the right type of sacrifice. Abel could not give life to the lamb, only God could do that. So the lamb represents the first sacrifice by man: a type of Christ, "...the first-fruits of them that slept."