John Calvin Commentary Psalms 105:44

"And he gave them the lands of the nations; And they took the labor of the peoples in possession:" — Psalms 105:44 (ASV)

And he gave them the countries of the nations. The Psalmist sets forth the ultimate purpose why God displayed His wonderful power in so many ways in redeeming the people, why He did not cease to cherish and defend them in the wilderness—why He gave them possession of the land as He had promised. This was so that they might dedicate and devote themselves completely to His service.

Indeed, the purpose God intended in our election was that He might have a people on earth by whom He would be called upon and served. To more effectively stir up the Jews to gratitude, the prophet magnifies the greatness of the divine goodness by declaring that they occupied far and wide the countries of the nations, and that all the property which many states had acquired with great labor, they now possessed, as it were, by right of inheritance. The plural forms of the words countries and nations serve to display the divine goodness in this matter in an even more striking light.

The psalm concludes by briefly defining the way to glorify God: That they might keep his law. It would not be enough to celebrate His grace only with the tongue. To this must be added practical and experiential piety. And since God rejects all religious services of human invention, the only way of rightly serving Him that remains consists in keeping His commandments.