We hence see the object of the Prophet; for he meant to express the greatest attention, as though he had said, that the faithful would ever wander in their thoughts, except they carefully concentrated both their eyes and their ears, and all their senses, on God, and continually restrained themselves, lest vagrant speculations or imaginations should lead them astray. And further, the Prophet teaches us, that we ought to have such reverence for God's word as to deem it sufficient for us to hear his voice. Let this, then, be our understanding, to obey God speaking to us, and reverently to embrace his word, so that he may deliver us from all troubles, and also keep our minds in peace and tranquillity.

God's speaking, then, is opposed to all the obstreperous clamours of Satan, which he never ceases to sound in our ears. For as soon as any temptation takes place, Satan suggests many things to us, and those of various kinds: "What will you do? what advice will you take? see whether God is propitious to you from whom you expect help. How can you dare to trust that God will assist you? How can he extricate you? What will be the issue?" As Satan then disturbs us in various ways, the Prophet shows that the word of God alone is sufficient for us all, then, who indulge themselves in their own counsels, deserve to be forsaken by God, and to be left by him to be driven up and down, and here and there, by Satan; for the only unfailing security for the faithful is to acquiesce in God's word.

But this appears still more clear from what is expressed at the close of the verse, when the Prophet adds, and what I may answer to the reproof given me; for he shows that he would be furnished with the best weapons to sustain and repel all assaults, provided he patiently attended to God speaking to him, and fully embraced his word: "Then," he says, "I shall have what I may answer to all reproofs, when the Lord shall speak to me". By "reproofs," he means not only the blasphemies by which the wicked shake his faith, but also all those turbulent feelings by which Satan secretly labors to subvert his faith. For not only the ungodly deride us and mock at our simplicity, as though we presumptuously and foolishly trusted in God, and were thus over-credulous; but we also reprove ourselves inwardly, and disturb ourselves by various internal contentions; for whatever comes to our mind that is in opposition to God's word, is properly a chiding or a reproof, as it is the same thing as if one accused himself, as though he had not found God to be faithful. We now, then see that the word "reproof" extends farther than to those outward blasphemies by which the unbelieving are wont to assail the children of God; for, as we have already said, though no one attempted to try our faith, yet every one is a tempter to himself; for the devil never ceases to agitate our minds. When, therefore, the Prophet says, what I may answer to reproof, he means, that he would be sufficiently fortified against all the assaults of Satan, both secret and external, when he heard what God might say to him.

We may also gather from the whole verse, that we can form no judgement of God's providence, except by the light of celestial truth. It is hence no wonder that many fall away under trials, yea, almost the whole world; for few there are who ascend into the citadel of which the Prophet speaks, and who are willing to hear God speaking to them. Hence, presumption and arrogance blind the minds of men, so that they either speak evil of God who addresses them, or accuse fortune, or maintain that there is nothing certain: thus they murmur within themselves, and arrogate to themselves more than they ought, and never submit to God's word.

~ John Calvin