The sacrifices of God are a broken and a contrite heart, that is aware of its own nothingness and helplessness (Psa.51:17). That is what Abel had, and what Cain did not have. And that is why it is written, "The Lord had regard for Abel, and (therefore) for his offering...... But the Lord had no regard for Cain and (therefore) not for his offering either (Gen.4:4,6).
Faith is the helpless dependence of the soul upon God and it was "by faith that Abel offered to God a better sacrifice than Cain" (Heb.11:4). Therefore Abel's gifts were acceptable to God.
There is a great deception in the teaching that what made the difference between Abel and Cain was that Abel offered blood and Cain did not. The application of such teaching is that what makes a man acceptable to God is his presenting the blood of Jesus before God. It is almost as though the way the man lives and the condition of his heart (whether broken or not, whether with faith or not) makes no difference. All he does is plead the blood of Jesus as though it were some type of magic charm, and he gains acceptance with God. This is a lie and many are being deceived by it.
The blood of Jesus cannot be claimed by anyone and everyone. It does NOT say in the Scriptures that the blood of Jesus can cleanse anyone and everyone from their sins. No. That is a subtle perversion of Scripture. What the Scripture does say is that the blood of Jesus will cleanse all those "WHO WALK IN THELIGHT AS GOD IS IN THE LIGHT" (1 Jn.1; 7). To walk in the light of God, one must have a broken and a contrite heart, as Abel had. Only then can one's offering be acceptable to God.
If a man says that he trusts in the blood of Jesus, but has a proud and arrogant spirit, God will resist him and oppose him (1 Pet.5:6), just like He did Cain. It is only the humble who receive grace from God (Jas.4:6).
Our offerings of worship, prayer and service are acceptable to God ONLY if they come from a broken and contrite heart of faith (humble dependence an God). It is not the fluency of our speech or the efficiency of our service that God looks at, but rather the attitude of our hearts. This is the first lesson that we can learn from this incident in Genesis 4.
From the days of Cain and Abel and on until the end of time, the sacrifices of God have always been a broken and contrite spirit. He does not change. His laws remain the same.
God would not have accepted Cain even if Cain had brought a lamb and shed its blood, for his heart was proud and lifted up.
Humility of heart is the first step to salvation Then we can come into the light and ask for the blood of Jesus to cleanse us from all sin.
It is only the humble of heart who can shout Paul's shout of triumph, "If God be for us, who can be against us " (Rom.8:31), because God is only on the side of the humble. The proud cannot say that, for God is against them. Anyone who has high thoughts concerning himself, as Cain had, will end up like Cain too, even if he keeps claiming the blood of Jesus. "Do not be deceived. God is not mocked; for whatever a man sows, this he will also reap" (Gal.6:7). And that law applies universally without respect of persons.