John Calvin Commentary Psalms 147:6

"Jehovah upholdeth the meek: He bringeth the wicked down to the ground." — Psalms 147:6 (ASV)

Raising up, etc. The ascription of this to God suitably tends to confirm our hope under affliction, and prevent our souls from fainting under the cross. From this we may infer that although our fathers who lived under the Law were more gently dealt with, they knew something at least of that warfare with which God daily disciplines us, in order to make us seek our true rest elsewhere than in this world.

Should a doubt steal upon the minds of those who have been brought under heavy afflictions regarding the arrival of that help which God has promised to extend, let us remember the truth that we are brought low so that God may lift us up again. And if, upon seeing the prosperity of the wicked, we are stricken and inflamed with envy, let the words of the Psalmist come into our mind: That they are lifted up so that they may be cast down into destruction. When he speaks of their being cast down even to the earth, there can be no doubt that he passes an indirect censure upon their pride, which leads them to exalt themselves on high, as if they belonged to some superior order of beings.