Relationship with God would be easier if He just did it on our terms. Cain felt the same way. When you read his story in the Bible, it’s easy to look at him as evil, decide that you are a far better person, and then go from there feeling far refreshed about your life. And happy that you aren’t wearing a loincloth, either.
If only it were that simple. What was the sin that first led Cain to the murder of Abel? Not giving to God in the manner God had prescribed. Abel brought to God His firstborn of the flock, the choicest lamb, and sacrificed it to the LORD. Cain brought some of his vegetables that he grew. The Bible doesn’t make them sound special or anything, so it probably wasn’t special. All of that added up to God not accepting Cain’s sacrifice, which led to anger, jealousy, and eventually murder.
Cain was not willing to give his best to God, or even his obedience. His desire was relationship on his own terms. God wants relationship on His terms, because He knows what is best for us and is ever willing to extend His good graces to us, provided that we are willing to accept His terms of relationship. The next time you have a chance to make an offering to God, make it your choicest, fattest offering, and give with a gracious heart, knowing well that God rewards those who seek His fellowship by giving them what they sought.