My kids and I were studying in Genesis when Cain murdered Abel. The question of why God rejected Cain’s sacrifice always seems to come first when reading these passages. Just about every explanation that I have heard has to do with the hearts of these brothers. One was pleasing to the Lord, one not. The book we are using right now for school focused on Genesis 4:3, which says, ‘In time, Cain brought an offering.’ Depending on the translation, that phrase, ‘in time’ can appear to mean one of a couple of things.
It could mean that once the boys grew up; it shows the significant passage of time that brings the brothers into an age of accountability. Or, and this is the meaning our study guide suggests, it refers specifically to Cain and in contrast to Abel. Cain, in time, brought an offering while Abel brought his first and best as an offering. The implication of this translation choice is that Abel put the Lord first, came to him in a timely manner with the best of the best to offer. Cain, on the other hand, gave a sacrifice when he got around to it, as it was convenient to himself. The Lord was not first. As a result, Abel’s offering was accepted and his brother’s rejected.
God is so good and faithful, we can count on it always coming down to the heart with Him. Two people can do the same thing, and the Lord sees right through their actions and knows the Truth. He knows our priorities, our first loves and He knows when we are merely giving lip-service to piety while living for ourselves.