Lord, my heart is not haughty - Though this is charged upon me; though I may have said things which seem to imply it; though this might appear a just inference from my conduct - yet I am conscious that this is not my real character. What I have said was not the result of ambition.
Nor mine eyes lofty - I am conscious that I am not ambitious and aspiring - as I am accused of being. What I have said is not the result of such a feeling, nor should such a charge be brought against me.
Neither do I exercise myself - Margin, as in Hebrew, walk. I do not walk about among such things; I do not pry into them; I do not meddle with them. What I have said or done is not, as has been said concerning me, the result of a meddlesome and interfering spirit. It may seem to be so; my own consciousness tells me it is not so. The interpretation put upon my conduct may be natural; but I am conscious to myself that it is not the right interpretation.
In great matters, or in things too high for me - Margin, as in Hebrew, wonderful. The word wonderful would apply to matters suited to excite astonishment by their vastness, or their unusual nature - as prodigies or miracles; and then, great and lofty truths. It would apply also to things which might be regarded as far above the capacity of a child, or of one in obscure life, and with slight advantages of education; and, as above suggested, it may have been the accusation brought against him, that, in respect to public matters, matters of state - or to the more elevated doctrines of religion - he had manifested a spirit unbecoming one in early years, and of humble rank, and that this indicated a desire to meddle with matters which he could not understand, and which could not pertain to him. He was conscious, he says, that he was not actuated by that spirit.

Surely I have behaved and quieted myself - Margin, as in Hebrew, my soul. The Hebrew is, “If I have not soothed and quieted my soul.” This is a strong mode of affirming that he had done it. The negative form is often thus used to denote a strong affirmation. The full form would be, “God knows if I have not done this;” or, “If I have not done this, then let me bear the consequences; let me be punished.” The idea is that he was conscious he had done this. Instead of being arrogant, proud, and ambitious - instead of meddling with matters above him, and which did not belong to him, he had known his proper place. He had been gentle, calm, retiring. The word rendered behaved means properly to be even or level; then, in the form used here, to make even, smooth, or level; and it is used here in the sense of calming the mind; smoothing down its roughnesses; keeping it tranquil. Compare the notes at Isaiah 38:13, in our version, “I reckoned” (the same word as here) “till morning,” but where the correct translation would be, “I composed or calmed myself until morning.” So the meaning here is, that he had kept his mind calm, and even, and gentle.
As a child that is weaned of his mother - See Isaiah 28:9. There have been very various interpretations of this passage. See Rosenmuller in loc. Perhaps the true idea is that of a child, when weaned, as leaning upon its mother, or as reclining upon her breast. As a weaned child leans upon its mother. That is, as a child, accustomed to the breast, and now deprived of it, lays its head gently where it had been accustomed to derive its nutriment, feeling its dependence, hoping to obtain nourishment again: not angry, but gently grieved and sad. A little child thus clinging to its mother - laying its head gently down on the bosom - languishing - looking for nourishment - would be a most tender image of meekness and gentleness.
My soul is even as a weaned child - literally, “As a weaned child upon me my soul;” that is probably, My soul leans upon me as a weaned child. My powers, my nature, my desires, my passions, thus lean upon me, are gentle, unambitious, confiding. The Septuagint renders this in a different manner, and giving a different idea, “Had I not been humble, but exalted myself as a weaned child doth against its mother, how wouldst thou have retributed against my soul!” The Hebrew, however, requires that it should be otherwise interpreted. The idea is, that he had been gentle; that he had calmed down his feelings; that whatever aspirations he might have had, he had kept them under; that though he might have made inquiries, or offered suggestions that seemed to savor of pride or ambition, he had been conscious that this was not so, but that he had known his proper place, and had kept it. The sentiment here is, that religion produces a child-like spirit; that it disposes all to know and keep their right place; that to whatever inquiries or suggestions it may lead among the young, it will tend to keep them modest and humble; and that whatever suggestions one in early life may be disposed to make, they will be connected with a spirit that is humble, gentle, and retiring. Religion produces self-control, and is inconsistent with a proud, an arrogant, and an ambitious spirit.

Let Israel hope in the Lord ... - The connection would seem to require us to understand this as the assertion of him who had been accused of thoughts which seemed to be too lofty. As the result of all his reflections (of those reflections for which he was rebuked and charged with pride, but which were really conceived in a modest spirit) - as expressing what he saw that seemed to be in advance of what others saw, or to indicate a habit of thought beyond his years - he says that there were reasons why Israel should hope in the Lord; that there was a foundation for confident trust; that there was that in the divine character which was a just ground of reliance; that there was that in the course of events - in the tendencies of things - which made it proper for the people of God, for the church, to hope, to confide, to feel assured of its ultimate and permanent safety. This would indicate the nature of the suggestions which he had expressed, and which had exposed him to the charge of arrogance; and it would also indicate a ripe and mature habit of thinking, beyond what might be expected from one in very early life. All this was, probably, applicable to David in his early years, as to the reflections which might have foreshadowed what he would be in future; this was eminently applicable to David’s Descendant - greater than he - who, at twelve years of age, astonished the Hebrew doctors in the temple with “his understanding and answers” Luke 2:47; this gives a beautiful view of modesty joined with uncommon gifts in early life; this shows what is always the nature of true religion - as producing modesty, and as prompting to hope.