Your life is a witness of the spiritual condition of your heart.
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: and by it he being dead yet speaketh. (Hebrews 11:4 (KJV)
This verse in Hebrews provides proof that both Cain and Abel understood exactly what offering God was looking for. This and this verse says “By faith Abel offered unto God a more excellent sacrifice than Cain….” Abel was familiar with being faithful. This clearly points to the fact that both boys had heard the Word of God but Abel offered a more pleasing sacrifice than Cain.
The Bible tells us faith comes by hearing the Word of God:
So then faith cometh by hearing, and hearing by the word of God. (Romans 10:17 KJV)
This verse is proof that Adam and Eve had taught Cain and Abel the truths of God as they were growing up. Cain chose to reject the Word of God and Abel abided in it. One took the narrow way; the other chose the wide avenue in this world. Cain chose to live according to his own way suppressing the Truth of God’s Word for the benefit of living according to his own will not according to the will of God for his life along the narrow corridor of God.