Proverbs 16:1

Proverbs 16:1-3 (see also Proverbs 21:1; Proverbs 24:12; Revelation 2:23)
The plans of the heart belong to man, but the answer of the tongue is from the LORD. All the ways of a man are clean in his own sight, but the LORD weighs the motives. Commit thy works unto the LORD, and thy thoughts shall be established. [KJV]

Similarly, Proverbs 16:9 states: “The mind of man plans his way, but the LORD directs his steps.” Proverbs 20:24 also states: “Man’s steps are ordained by the LORD, How then can man understand his way?” This shows that there is a divine purpose and plan to life, and that life is heading toward a predetermined divine objective, and while any mediocre deity could easily govern a race of dumb marionettes, it takes a truly all-powerful, all-knowing and all-wise God to be able to govern those whom He created without strings and designed with autonomy of reason, so that by steering all possibilities and every conceivable scenario, a desired end may be reached, despite the efforts of any meddling being who might otherwise wish to thwart His plan. Such perfect omnipotence allows the created order to do as it will, while the Divine does His, all in directing creation towards a final goal.

While the text contrasts “the plans of the heart belong to man” with “the answer of the tongue is from the Lord,” in Calvinism, the text might as well instead state: “The plans of the heart and the answer from the tongue are both from the Lord” as both would be equally decreed.

One men’s devotional explains: “The world will often lead you astray, but God will not. His counsel leads you to Himself, which, of course, is the path He has always intended for you to take. Are you facing a difficult decision, a troubling circumstance, or a powerful temptation? If so, it’s time to take a step back, to stop focusing on the world, and to focus, instead, on the will of your Father in heaven. Everyday living is an exercise in decision-making. Today and every day you must make choices: choices about what you will do, what you will worship, and how you will think. When in doubt, make choices that you sincerely believe will bring you to a closer relationship with God. And if you’re uncertain of your next step, pray about it. When you do, answers will come—the right answers for you.” (Journey with God)

One member of The Society of Evangelical Arminians comments:The opposite is also true: Do not commit your works to the LORD, and your plans will not be established.” (SEA)

Another member of The Society of Evangelical Arminians comments:When it comes to the answer of the tongue, this is not different from Jesus’ promise that the Holy Spirit would help the disciples with what to say when they are arrested, and implies a broader set of circumstances under which the Spirit would help men with what they say. Ditto for a man’s steps, where the man decides or realizes where he needs to go, but needs God to help him get there. Contrast with Thomas saying to Jesus ‘How do we know the way?’ In both cases, God says, ‘I am the way, the truth, and the life.’” (SEA)

This seems to be a very clear explanation, though Calvinists see Determinism:

John Calvin writes:Whatever things are done wrongly and unjustly by man, these very things are the right and just works of God. This may seem paradoxical at first sight to some....” (Concerning the Eternal Predestination of God, p.169, emphasis mine)

Calvin writes: “But where it is a matter of mens counsels, wills, endeavours, and exertions, there is greater difficulty in seeing how the providence of God rules here too, so that nothing happens but by His assent and that men can deliberately do nothing unless He inspire it.” (Concerning the Eternal Predestination of God, pp.171-172, emphasis mine)

Calvin writes: “Indeed, the ungodly pride themselves on being competent to effect their wishes. But the facts show in the end that by them, unconsciously and unwillingly, what was divinely ordained is implemented.” (Concerning the Eternal Predestination of God, p.173, emphasis mine)

Calvinist, James White, responds: “...since God judges on the basis of the intentions of the heart, there is in fact a ground for morality and justice.” (Debating Calvinism, p.320, emphasis mine)

Dave Hunt responds: “Yes, God judges ‘the intentions of the heart,’ but Calvinism falsely says that He causes the intentions He judges.” (Debating Calvinism, p.327, emphasis mine)

Dave Hunt writes: “...‘the LORD pondereth the hearts--a meaningless statement if God decrees every thought, word, and deed. What would He ponder?” (Debating Calvinism, p.129, emphasis mine)

Proverbs 24:12: If you say, ‘See, we did not know this,’ does He not consider it who weighs the hearts? And does He not know it who keeps your soul? And will He not render to man according to his work?

Revelation 2:23: I am He who searches the minds and hearts; and I will give to each one of you according to your deeds.

The problem with Deterministic Calvinism, which presupposes an all-encompassing decree, in which all things unfold according to a script, is that it leaves nothing for God to search” and weigh. What would God be weighing? Would He be searching for what He predestined? How would that make sense?