I will instruct thee, and teach thee in the way that thou mayest walk: I will counsel thee with
mine eye. Be not like the horse or mule, which have no understanding: thou shalt bind his
jaw with bit and bridle, lest they kick against [or become obstreperous against or obstinately
disobey] thee. Many sorrows shall be to the wicked: but the man who hopeth in Jehovah, mercy shall surround him. Be glad in Jehovah, and rejoice, ye righteous: sing all ye that are upright in heart.
"I will instruct thee, and teach thee." That his exhortation may have the greater force, the divine speaker directs his discourse to every man individually; for the doctrine which is spoken penetrates the mind more readily, when every man applies it particularlyto himself. When the way of salvation is here shown to the children of God, the greatest care must be taken that no man depart from it in the slightest degree. We may also learn from this place, that we are reconciled to God upon condition that every man endeavor to make his brethren partakers of the same benefit. David, the more strongly to mark his care about them, describes it by the sight of the eye. By the way it should be observed, that those who are solicitous about our welfare are appointed by the Lord as guides of our way, from which it appears how great is the paternal solicitude which he has about us.
"Be not like the horse or mule." David now briefly explains the amount of the counsel which he formerly said he would give. He exhorts all to learn with quietness, to lay aside stubbornness, and to put on the spirit of meekness. There is much wisdom, too, in the advice which he gives to the godly to correct their hardihood; for if we were as attentive to God’s corrections as we ought, every one would eagerly hasten to seek his favor. Whence is so much slowness to be found in all, but that we are either stupid or refractory? By likening the refractory, therefore, to brute beasts, David puts them to shame, and at the same time declares that it will avail them nothing to “kick against the pricks.” Men, says he, know how to tame the fierceness of horses by bridles and bits; what then do they think God will do when he finds them intractable?
..."Be glad in Jehovah." After teaching how ready and accessible true happiness is to all the godly, David, with much reason, exhorts them to gladness. He commands them to rejoice in the Lord, as if he had said, There is nothing to prevent them from assuring themselves of God’s favor, seeing he so liberally and so kindly offers to be reconciled to them. In the meantime, we may observe that this is the incomparable fruit of faith which Paul likewise commends, namely, when the consciences of the godly being quiet and cheerful, enjoy peace and spiritual joy. Wherever faith is lively, this holy rejoicing will follow. But since the world’s own impiety prevents it from participating in this joy, David, therefore, addresses the righteous alone, whom he denominates the upright in heart, to teach us that the external appearance of righteousness which pleases men is of no avail in the sight of God. But how does he call those righteous, whose whole happiness consists in the free mercy of God not imputing their sins to them? I answer, that none others are received into favor but those who are dissatisfied with themselves for their sins, and repent with their whole heart; not that this repentance merits pardon, but because faith can never be separated from the spirit of regeneration. When they have begun to devote themselves to God, he accepts the upright disposition of their hearts equally as if it were pure and perfect; for faith not only reconciles a man to God, but also sanctifies whatever is imperfect in him, so that by the free grace of God, he becomes righteous who could never have obtained so great a blessing by any merit of his own.