When ye offer me sacrifices and your gift, etc. מנחה, meneche, properly means a gift of flour, which was an addition to the sacrifice; but it is often taken generally for any kind of offering. It is indeed certain that the Prophet meant, that however much the Israelites accumulated their ritual observances, they did nothing towards appeasing God, inasmuch as they observed not the law that was given them; and they turned also to a wrong purpose their sacrifices; for they did not exercise themselves in piety and in the spiritual worship of God, but, on the contrary, spread veils before God, that by presenting a fictitious form of worship, they might cover all their sins; for they thought themselves to be hidden from God.
This is the reason why the Prophet declares that these offerings would not be received by God, לא ארצה, la areste, I will not accept them. The Prophet no doubt alludes here to those promises, which are to be found everywhere in the law, as he did when he said in the last verse, לא אריח, la arich, I will not smell רוחה, ruch, means to smell; and Moses often uses the expression, that God is delighted with the odour of sacrifices, or with the smell of incense. But when the Lord declares that odour is pleasant to him, he means that it is so, provided the people sacrificed rightly, that is, when they brought not sacrifices as false veils to cover their sins, but as true and real evidences of their faith and repentance; God promised in that case that sacrifices would be a sweet odour to him. Now, on the contrary, he declares that the perfume would not be acceptable to him, nor sacrifices appeasing. But sacrifices not only were acceptable to God, but also pacified him. Since then the Lord had so often said, that he would be propitious to his people, when sacrifices were offered, it was necessary expressly to cut off this confidence from the Israelites, when they dealt not faithfully with God. God never disappointed his true worshipers, but ever received them into favor, provided they approached him in sincerity. But as these hypocrites dealt falsely with him, they were necessarily disappointed of their hope, as the Prophet here declares.
The peace-offerings of your fat things, he says, I will not regard God indeed promised in the law that he would regard their sacrifices provided they were lawful; but as the Israelites had in two ways departed from pure worship, God now justly says, I will not look on your sacrifices, nor on the peace-offerings of your fat things He calls them the peace-offerings of fat things, intimating, that though the beasts were the choicest, they would not yet be acceptable to him; for the Lord regards not fatness, as he needs neither meat nor drink. Then, in a word, the Prophet here sets this fatness in opposition to true godliness and obedience too. In both respects there was, as we have seen, a defect among the Israelites; for they obeyed not the law as to its outward requirements, and their hearts were impure and perverse: hence all their sacrifices were necessarily polluted and corrupt.