What does it mean to lean not on your own understanding (Proverbs 3:5)?

Verses 5 and 6 were deeply impressed on the writer at an early age, and have no doubt spoken seriously to many others before and since that time. There are many things in which our understanding is extremely faulty, and if we depend on it, we shall be badly misled. the only safe alternative is to trust in the Lord with all our heart. that is, fully and without reserve. He will certainly not deceive us, nor is there any possibility of His making a mistake.

The whole heart certainly involves all of our ways. In every activity we should acknowledge Him, so that nothing is left simply to our own judgment. If this is so, we may have full confidence that He will direct our paths (v. 6). If we are tempted to think, because we have proven something of God's gracious guidance, that we are wise (v. 78), let us judge this immediately, but instead realize that it is only by God's wisdom that we are blessed. On our part, we are to "fear the Lord and depart from evil." If the Lord is given His place, then we recognize that evil can have no place. This response to the Lord will mean "health to your flesh and strength to your bones" (v. 8). Of course, this is not merely literal. The bones are the framework of the body, so that spiritual health and strength are implied in this, the body being the daily activity, the bones the strength by which the activity is carried out.

Yet we are told to “cease from thine own wisdom,” which means that wisdom cannot be rightly used save as you “trust in the Lord with all thine heart”—wisdom must not be divorced from real communion with and dependence upon the Lord.

Cursed is man that trusts in man, says the prophet (Jer. 17:5), and he that trusts his own heart is a fool (Prov. 28:26). “Trust in the Lord with all thine heart, and lean not unto thine own understanding” (Prov. 3:5) God has set man in dependence upon Himself, and therefore no one needs think himself quite competent to take up eternal problems, and to solve them by his own natural intelligence; for should he make any such attempt he is as certain to go astray as though to go astray was the one desire of his heart.

He now enters into details in verses 5 and following. Two paths are before man - to trust God, or himself and his own wisdom for his happiness. This is just what Eve failed in; she did not confide in God, trust in Him and what He had said, for her happiness, but leaned to her own understanding, thought she should better secure it by doing what she thought would be advantageous. So every sinner; he thinks he can better secure his own happiness in doing his own will than in listening to God. Trust in God is the first positive active principle of life and wisdom; the next is owning Him in our ways, taking His will, authority, as that which is to form them, not our will and wisdom, and that openly (v. 6). He will surely direct our steps. No human wisdom can guide like that. It may be very cunning - know human nature. But God has a way which He has laid down morally for us - a path of obedience, of righteousness, and of God; and He who has done so orders all things. In the end His judgment will prevail. We may not see it prevail here - thus faith may be exercised; where His direct government is exercised, it will, but always in result. The end of the Lord is sure; heaviness may endure for a night, for a season if need be; but, for the faithful soul, joy comes in the morning, a morning near to come. But self-confidence is ruin. "Be not wise in thine own eyes" (v. 7). They do not see far if they only see self, and that is what always is in our own eyes. The fear of God, as we have seen, the moral path of His fear, is that on which He waits in goodness, however things may seem - this, and departing from all evil. This is something more than walking in His fear - there is an abhorrence of evil, partly in itself, partly as contrary to His will. I may walk in God's fear, do no evil myself, without, I think, being characterised by departing from evil. No doubt, walking rightly is not doing evil. But evil is in the world, and there is, so to speak, a positive character of relationship to it, that is, departing from it, abhorrence of it. Adam, innocent, would have walked uprightly, done nothing wrong; he would not have departed from evil, he had nothing to say to it. I have or may have. I depart from it, leave and break with it. This has to do with holiness. We have seen Jehovah owned by confidence, and in His servant's ways. It requires confidence in Him to guide one's ways by His will. Now we come to another way of owning devotedness of heart, owning all positive good and blessing to come from Him, and manifested in the ready but due offering of a willing heart. Thus blessing is found, temporal blessing; v. 8-10. It must be remembered that we are always here on the ground of present government in the earth. Higher objects may bring sorrow as regards this world, as it has ever been. Now we can only apply the principle. Peter's epistles give the degree in which this government applies to Christian standing.

Yes, it was good and right to trust in Jehovah with all the heart, and to lean not on one's own discernment, as the tempter always advises to ruin, sorrow, and shame. This is the divine counsel for the heart. But the Israelite needed also to "acknowledge Him" in all his ways. And the heart if loyal would prompt to honour Him thus. For practical inconsistency is a burden to the upright; and it is due to Jehovah to own Him where He is apt to be ignored or forgotten in each detail of walk, and in them all. Nor was it even without present fruit, for He could not be unmindful, who never slumbers or sleeps. "And He shall make straight thy paths." He is Lord of all, no less than He is the Eternal, and concerns Himself with every obstacle and difficulty for such as would walk unswervingly according to His will.

In the path of God's will mere human wisdom and understanding will not avail. It is "a path which no fowl knows, and which the vulture's eye has not seen: the lion's whelps have not trodden it, nor the fierce lion passed by it" (Job 28:7-8). No eye so keen in nature as the vulture's; no animal so bold as the lion. But the boldness and long-sightedness of nature are not equal for the path of faith. Singleness of eye that has Christ for its only Object will alone give spiritual understanding.

But it must be borne in mind that, in order to profit by divine guidance, there must be the abandonment of our own will, and of all confidence in our own reasonings, as well as all confidence in the thoughts and reasonings of others. If I have Jehovah as my Guide, I do not want my own eyes or the eyes of a Hobab either. God is sufficient: I can trust Him. He knows all the way across the desert; and hence, if I keep my eye upon Him, I shall be guided aright.

Therefore a mere study of the Word, however necessary it be to study it, is not of itself sufficient to place us in possession of the thoughts of God. It is necessary that we should read it, pay attention to all that it brings before us, believe it even when we do not grasp its meaning, and meditate upon its precious utterances; but this should be done in prayerful dependence upon its gracious Author, and in distrust of our own natural reason, which is always infidel, and always infidel just because it is our reason, the reason of fallen flesh, which ever revolves in its own blind orbit, excluding every ray of light divine.

Thus God would teach us the lesson of dependence, and how we should ever seek His guidance. We are not sufficient of ourselves to map out our own paths, whether as individuals, or in relation to the Church of God. How full of thoughtful care are all God's ways. We may well trust Him to do far better for us than we can do for ourselves.

Now it was in the absence of Moses that the trouble arose in the camp (Exodus 32). “The man that trusts in his own heart is a fool,” because he leaves God out of account. He allows the prejudices of his own opinions and the pride of his own desires to influence him rather than the word of God. He is governed by the sight of his eyes rather than the faith of his heart.