In Genesis 4 we see two kinds of examples. Abel was an excellent example of believing the gospel, practicing the gospel, and living for the gospel. Cain, the firstborn of the second human generation, was an example of continuing the fall and of turning from God's way of salvation. With Adam and Eve there were two main matters: the fall which they caused and the gospel which they received and preached. Adam and Eve were saved, and they passed on the word of salvation to the following generation. We also must share these things with our own children, telling them the sad story of man's fall and proclaiming to them the good news of God's salvation. Cain did not follow the way of God's salvation, but continued the fall. His life was a continuance and a furtherance of man's fall. Therefore, we may say that with Cain mankind experienced a second fall. His parents caused the first fall; he continued it and brought about the second.
Here I would speak a word of warning: Never continue the fall. We must separate ourselves from the fall and say to it, "Fall, I refuse to cooperate with you. Stay away from me. I will not allow you to continue. I will run to God's salvation." Cain perpetuated man's fall, but Abel pursued God's way of salvation. The same choice confronts us today. Do you want to remain in the fall and continue it or will you go to God for salvation? We should not be so unwise as to continue the fall. We must accept God's provision for our salvation. Nevertheless, Cain was foolish, remaining in the fall and actually abetting its development.
We need to understand the cause of man's second fall. One reason for Cain's continuing the fall was that the Devil had gained him inwardly. Apparently it was Cain that rejected God's glad tidings; actually it was Satan that kept him from God's way of salvation. Satan knew that if Cain had received the glad tidings he would have had no way to gain him. Hence, he subtly caused Cain to take his own way of worshipping God. By this means he kept Cain in his hand and even caused him to fall further. Thus, the second fall of man was instigated by the subtle one who had gained Cain and worked within him.
At the time of Genesis 4 the Devil had already injected himself into man, and God had shown man His way of salvation. However, Cain was presumptuous in that he forsook God's way of salvation. This means that he followed the Devil and put aside God's will. This was a further cause of the second fall. Cain did not care for God's Word, for God's gospel, and he did not hearken to the preaching of his parents. Once again I say that I strongly believe that his parents preached the gospel to him and his brother, telling them of their need for coverings made from the skins of the sacrificial lambs. I believe that this accounts for Abel's desire to be a feeder of the sheep. However, Cain had no regard for this, presumptuously forsaking God's way and inventing his own.