John Calvin Commentary Psalms 119:32

"I will run the way of thy commandments, When thou shalt enlarge my heart. HE." — Psalms 119:32 (ASV)

I will run the way of thy commandments. The prophet's meaning is that when God will inspire him with love for his law, he will be vigorous, ready, and even steady, so that he will not faint in the middle of his course. His words contain an implied admission of the passive inability of humans to make any advancement in doing good until God enlarges their hearts.

As soon as God expands their hearts, they are fitted not only for walking but also for running in the way of his commandments. He reminds us that the proper observance of the law consists not merely in external works, but that it also demands willing obedience, so that the heart must, to some extent and in some way, enlarge itself.

This is not to say that the heart has the self-determining power to do this; but once its hardness and obstinacy are subdued, it moves freely, no longer contracted by its own narrowness. Finally, this passage tells us that once God has enlarged our hearts, there will be no lack of power, because, along with proper affection, he will furnish ability, so that our feet will be ready to run.