A manual for making decisions, disguised as a proverb.

You likely know these lines by heart. Matthew Henry treated them as something you can use — a working method for the choice sitting on your desk right now.

Trust in the Lord with all your heart and lean not on your own understanding; Proverbs 3:5 · New International Version

Proverbs 3:5–6 reaches most readers as familiar lines; Henry treats the pair as a manual for making decisions. Unfold the method a step at a time.

What trusting with all your heart actually is

Trusting with all your heart, Henry says, means to repose an entire confidence in the wisdom, power, and goodness of God, believing that he is able to do what he will, wise to do what is best. Notice what that asks of you: not a feeling, but a transfer of weight. The confidence you would otherwise rest on your own read of the situation goes, whole, onto God.

The diagnosis underneath the warning

The warning against leaning on your own understanding is not anti-intellectual; it is diagnostic: Those who know themselves cannot but find their own understanding to be a broken reed, which, if they lean to, will certainly fail them. Henry balances the two postures in one sentence — be diffident of our own judgment, and confident of God's wisdom, power, and goodness.

A rule of motion for the waiting weeks

Then Henry hands you a rule of motion: follow Providence and not force it, adding the proverb-within-a-proverb, That often proves best which was least our own doing. If you have ever watched a door you did not push swing open, you have seen what he means.

in all your ways submit to him, and he will make your paths straight. Proverbs 3:6 · New International Version
Acknowledging him: wide-coverage prayer

Acknowledging God in all your ways, Henry says, is wide-coverage prayer. We must ask his leave and ask his advice and beg direction from him — not only in hard cases but in every case, be it ever so plain — and then patiently, and with a holy indifferency, wait his award. His word award means God's decision, not a prize: you are waiting on a verdict you have agreed in advance to accept.

Both kinds of road are covered

Ways that prosper call for acknowledging God with thankfulness; ways hedged with difficulty, for acknowledging God with submission. And the promise at the end is as wide as the trust it asks for: Those that put themselves under a divine guidance shall always have the benefit of it.