Keil & Delitzsch, on Isa 11:3

And His regal conduct is regulated by this His thoroughly spiritual nature."And fear of Jehovah is fragrance to Him; and He judges not according to outward sight, neither does He pass sentence according to outward hearing." We must not render it: His smelling is the smelling of the fear of God, i.e., the penetration of it with a keen judicial insight (as Hengstenberg and Umbreit understand it); for hērı̄ach with the preposition Beth has not merely the signification to smell (as when followed by an accusative, Job 39:25), but to smell with satisfaction (like בּ ראה, to see with satisfaction), Exo 30:38; Lev 26:31; Amo 5:21. The fear of God is that which He smells with satisfaction; it is rēach nı̄choach to Him. Meier's objection, that fear of God is not a thing that can be smelt, and therefore that hērı̄ach must signify to breathe, is a trivial one. Just as the outward man has five senses for the material world, the inner man has also a sensorium for the spiritual world, which discerns different things in different ways. Thus the second David scents the fear of God, and only the fear of God, as a pleasant fragrance; for the fear of God is a sacrifice of adoration continually ascending to God. His favour or displeasure does not depend upon brilliant or repulsive external qualities; He does not judge according to outward appearances, but according to the relation of the heart to His God.