Charles Ellicott Commentary Genesis 4:3-4

"And in process of time it came to pass, that Cain brought of the fruit of the ground an offering unto Jehovah. And Abel, he also brought of the firstlings of his flock and of the fat thereof. And Jehovah had respect unto Abel and to his offering:" — Genesis 4:3-4 (ASV)

In process of time. —Hebrew, at the end of days: not at the end of a week, or a year, or of harvest-time, but of a long indefinite period, shown by the age of Adam at the birth of Seth to have been something less than 130 years.

An offering. —Hebrew, a thank-offering, a present. We must be careful not to introduce here any of the later Levitical ideas about sacrifice. All that we know about this offering is that it was an act of worship, and apparently something usual. Now, each brought of his own produce, and one was accepted and one rejected. Why? Much ingenuity has been wasted on this question, as though Cain erred on technical grounds; whereas we are expressly told in Hebrews 11:4 that Abel’s was the more excellent sacrifice, because offered in faith. It was the state of their hearts that made the difference; though, as the result of unbelief, Cain’s may have been a scanty present of common produce, and not of first-fruits, while Abel brought firstlings, and of the fat thereof, the choicest portion.

Abel may also have shown a deeper faith in the promised Deliverer by offering an animal sacrifice; and certainly, the acceptance of his sacrifice stimulated among people the belief that the proper way of approaching God was by the death of a victim. But Cain’s unbloody sacrifice also had a great future before it. It became the minchah of the Levitical law, and under the Christian dispensation is the offering of prayer and praise, and especially the Eucharistic thanksgiving.

We have already noticed that Abel’s sacrifice shows that flesh was probably eaten on solemn occasions. If animals had been killed only for their skins for clothing, repulsive ideas would have been connected with the carcasses cast aside to decay, nor would Abel have attached any value to firstlings. But as soon as the rich abundance of Paradise was over, humankind would quickly learn to supplement the scanty produce of the soil by killing wild animals and the young of their own flocks.

The Lord had respect. —Hebrew, looked upon, showed that He had seen it. It has been supposed that some visible sign of God’s favour was given, and the current idea among the fathers was that fire fell from heaven and consumed the sacrifice . But there is real irreverence in thus filling up the narrative; and it is enough to know that the brothers were aware that God was pleased with the one and displeased with the other.

It is more important to notice, first, that God’s familiar presence was not withdrawn from humanity after the fall. He talked with Cain as kindly as with Adam of old. Second, in these earliest records of humankind, religion is built upon love, and the Deity appears as humanity’s personal friend. This contradicts the scientific theory that religion grew out of dim fears and terror at natural phenomena, gradually ending in the evolution of the idea of a destructive and dangerous power outside of humanity, which humanity had to propitiate as best it could.