But in order to arrive at its full meaning, we must suppose that David felt an inward struggle and opposition, which he found it necessary to check. Satan had raised a tumult in his affections, and wrought a degree of impatience in his mind, which he now curbs; and he expresses his resolution to be silent. The word implies a meek and submissive endurance of the cross. It expresses the opposite of that heat of spirit which would put us into a posture of resistance to God. The silence intended is, in short, that composed submission of the believer, in the exercise of which he acquiesces in the promises of God, gives place to his word, bows to his sovereignty, and suppresses every inward murmur of dissatisfaction.
–From his commentary on the Psalms, and quoted by yours truly in this morning’s sermon