John Calvin Commentary Isaiah 11:3

"And his delight shall be in the fear of Jehovah; and he shall not judge after the sight of his eyes, neither decide after the hearing of his ears;" — Isaiah 11:3 (ASV)

And will make him sagacious. The verb ריח (riach), which is used here in the Hiphil conjugation, literally means to smell. However, it can also be explained in an active sense, meaning to give a keen smell. I think this interpretation agrees better with this passage, allowing this sagacity to also be included among the gifts of the Spirit.

This effect is especially applicable to the person of Christ: namely, that far beyond what the godly are able to conceive, he is endowed with shrewd discernment for governing his people. We should pay attention, first of all, to the metaphor in the verb smell. This metaphor means that Christ will be so shrewd that he will not need to learn from what he hears or from what he sees, for by smelling alone he will perceive what would otherwise be unknown.

In the fear of the Lord. Most commentators view this phrase as meaning that all the feelings of the heart will be clear to Christ, so that he will easily judge who are the sincere worshippers of God. But the reader should consider whether it is not a more appropriate meaning that the fear of God denotes a fixed rule of judging. He expressly distinguishes between the heavenly judgment of Christ and earthly judgments, to inform us that the outward mask of holiness or uprightness is of no avail in his presence.

And he shall not judge after the sight of his eyes. The meaning is, “When we come to the judgment-seat of Christ, not only will outward actions be brought to trial as in human governments, but the lives of people will be examined by the standard of true godliness. It is not for humans to penetrate hearts; and those whom we suppose to be very excellent people frequently have nothing but a hollow mask. But Christ does not judge from outward appearance (Luke 11:17; John 2:25), for he thoroughly knows and searches our inmost thoughts. His judgment, therefore, is quite different from that of humans, who, with all their acuteness and quick sagacity, fall into the most shameful mistakes.”

Hence it follows that only those whom Christ approves can be the true worshippers of God. They cannot obtain his approval unless they offer a pure and upright mind, for a false and hollow mask cannot deceive him.