Many of us are "Cains." Fallen human nature raises Cain. Our flesh tends to follow the attitude that Cain displayed toward God. In Genesis 4, Cain offers to God what he wants to give. In contrast, Abel offers to God what God really wants. As "Cains," we do things for others and for God, but it is only what we want to give, not necessarily what the other really wants.
Man-made religion performs various rituals and practices in order to gain God's favor. However, the truth is God has already chosen us and given us His infinite favor. This revealed love, “while we were still sinners, Christ died for us” (Romans 5:8), is not earned, just given. All God seeks is for man to receive what Jesus has done and come into a loving relationship with Him. Our only honest and humble response is to honor Him by choosing to do what He wants. In one word, obey.
We would rather do things for God than obey from the heart. Yet, Samuel reminds us, "Obedience is better than sacrifice." Even when describing Jesus in Hebrews 10, the Word states that "sacrifices and offerings You did not desire," but rather, "Behold, I have come to do Your will, O God."
Obviously coming to do God's will is what God desires.
Our challenge is simple. Rather than adopting the "give only what I want" attitude of Cain, find out what God really wants and simply do it.