John Calvin Commentary Psalms 119:13

"With my lips have I declared All the ordinances of thy mouth." — Psalms 119:13 (ASV)

With my lips In this verse, he declares that God's law was not only deeply engraved on his own heart, but that it was also his earnest and strenuous effort to win over many of his fellow disciples to submission to God. It is indeed an empty matter to speak of God's law abstractly, as we see hypocrites do, who speak very fluently about the entire doctrine of godliness, to which they are complete strangers.

What the prophet observed above, regarding the heart's affection for God’s law, he now also applies to the lips. And, immediately after, he again establishes the truth of what he had asserted about his sincere and genuine efforts to instruct others, by saying that he derived no less pleasure from God's doctrine than from all the riches of the world.

He indirectly contrasts his holy love for the law, with which he was inflamed, with the unholy greed that has taken hold of almost the entire world. “As wealth attracts people's hearts, so I have found more exquisite delight in the progress I make in the doctrine of godliness, than if I abounded in all kinds of riches.”