John Calvin Commentary Psalms 147:7

"Sing unto Jehovah with thanksgiving; Sing praises upon the harp unto our God," — Psalms 147:7 (ASV)

Sing to Jehovah in thanksgiving. Again, he exhorts us to sing the praises of God, suggesting at the same time that there was no lack of abundant reason, since new proofs of his power, goodness, and wisdom continually appear before our eyes. First, he tells us that he covers the heavens with clouds, and this change would awaken our attention, if we were not so thoughtless.

As varied as the marvels to be seen in the heavens above us are, if the same serenity were always to continue, we would not have such a wonderful display of his power as when he suddenly veils them with clouds, withdrawing the light of the sun, and setting a new face, as it were, upon the world.

He afterward suggests that in this way provision is made for all living creatures, for by this means the herbs germinate, and the earth is supplied with the moisture that makes it fertile. Thus, in connection with the proofs of his power, God sets before our eyes those of his mercy and fatherly consideration for the human family; indeed, he shows that he does not overlook even the wild animals and cattle.

Philosophers discover the origin of rain in the elements, and it is not denied that clouds are formed from the dense vapors that are exhaled from the earth and sea. However, secondary causes should not prevent us from recognizing the providence of God in providing the earth with the moisture needed for fruitfulness.

Just as the earth, parched by heat, shows its thirst by opening its mouth, so God, on his part, in sending rain, distills drink for it. He might, in other, more hidden ways, give it strength to keep it from failing, but this irrigation is something that passes before our eyes to visibly portray the continual care he has for us.