John Calvin Commentary Psalms 17:5

"My steps have held fast to thy paths, My feet have not slipped." — Psalms 17:5 (ASV)

Uphold my steps. If we take God’s paths as the precepts of His law, the meaning will be evident: namely, that although David had spoken truthfully, boasting of having constantly practiced righteousness with a pure heart in the midst of the most grievous temptations that assailed him, yet, conscious of his own weakness, he commits himself to God to be governed by Him, and prays for grace to enable him to persevere.

His language is as if he had said, "Since until now, under Your guidance, I have proceeded onward in the right path, I beseech You, in like manner, to keep my steps from sliding in the future." And certainly, the more anyone excels in grace, the more he ought to be afraid of falling, for it is the usual policy of Satan to endeavor, even from the virtue and strength that God has given us, to produce in us carnal confidence that may induce carelessness.

I do not altogether reject this meaning, but I think it more probable that David here beseeches God to bring his affairs to a prosperous outcome, however dark the present situation appeared.

The meaning of his language is this: "Lord, since You see that I walk in uprightness and sincerity of heart, govern me in such a way that all people may see that You are my protector and guardian, and do not leave me to be cast down by my enemies' will."

Thus, by the paths of the Lord, he means not the doctrine that regulates our life, but the power by which God upholds us and the protection by which He preserves us.

And he addresses God in this manner, not only because all events are in His hand, but also because when He takes care of us, all things in our lives go prosperously. When he adds, that the soles of my feet may not slide, he refers to the many adverse events that threaten us every moment, and to the danger we are in of perishing if not sustained by the hand of God.