10. As the Lord commanded. Of all this Moses was an interested observer. He was the one with whom the Lord had communicated and who had instructed Aaron and his sons in what they were to do. Now he watched to see that all things were done according to God’s instructions. It would have been a serious mistake for Aaron to sprinkle the blood of the sin offering upon the altar round about. That must never be done. The blood of the sin offering must be put on the horns of the altar. Again, it would be a serious mistake to put the blood of the burnt offering upon the horns of the altar. That must never be done. The blood of the burnt sacrifice was always sprinkled on the altar round about. The symbolism demanded that everything be done in exactly the manner God had prescribed. Aaron therefore made no mistake.