Thy mercy, O Lord, is in the heavens - This commences the second part of the psalm - the description of the character of God in contrast with the character of the wicked man. The meaning here is, evidently, that the mercy of God is very exalted; to the very heavens, as high as the highest object of which man can conceive. Thus, we speak of virtue as “exalted,” or virtue of the “highest kind.” The idea is not that the mercy of God is “manifested” in heaven, for, mercy being favor shown to the guilty, there is no occasion for it in heaven; nor is the idea that mercy, as shown to man, has its “origin” in heaven, which is indeed true in itself; but it is, as above explained, that it is of the most exalted nature; that it is as high as man can conceive.
And thy faithfulness - Thy “truthfulness;” thy fidelity to thy promises and to thy friends.
Reacheth “unto the clouds.” The clouds are among the highest objects. They rise above the loftiest trees, and ascend above the mountains, and seem to lie or roll along the sky. The idea here, therefore, as in the first part of the verse, is, that it is elevated or exalted.