John Calvin Commentary Psalms 119:10

"With my whole heart have I sought thee: Oh let me not wander from thy commandments." — Psalms 119:10 (ASV)

With my whole heart. Conscious of the integrity of his heart, the prophet still implores God's help, so that he might not stumble because of his weakness. He makes no boast of self-preparation, as if he had spontaneously begun to seek God; but in praising the grace he had experienced, he at the same time aspires to steadfastness to persevere in walking in His ways. It is folly on the part of Roman Catholics to seize upon this and similar passages, as if the saints, by their own free will, anticipated the grace of the Holy Spirit and were afterwards favored with His aid. The prophet does not make a division between God and himself, but rather prays for God to continue His work until it is completed, consistent with what we are generally taught: to keep God mindful of His benefits until He accomplishes them.

Meanwhile, there is good reason for presenting our supplication to God, asking Him to extend His hand to us when He sees our minds so resolved that our greatest concern is to act uprightly. And just as He gives us confidence to ask for the gift of perseverance when He inspires our hearts with proper affection toward Him, so also He urges us in the future not to sink into a careless and listless state, like soldiers who have been discharged, but to seek to be constantly directed by the spirit of wisdom and sustained by the principles of fortitude and virtue.

David here, by his own example, points out a rule to us: the more a person finds himself helped by God, the more he should be moved to implore more carefully and earnestly the continuation of His aid. For unless He restrains us, we will instantly wander and go astray. This sentiment is more explicitly stated in the original word תשגני, tashqeni, which is in the passive voice and means to be led astray. From the meaning of the term, I do not mean to establish the doctrine that God secretly incites us to commit sin, but only to let my readers know that our liability to err is so great that we immediately relapse into sin the moment He leaves us to ourselves. This passage also admonishes us that whoever swerves even a little from God’s commandments is guilty of going astray.