Trust in the LORD with all thine heart; and lean not unto thine own understanding.
Ver. 5. Trust in the Lord.] To trust in God is to be unbottomed of thyself, and of every creature, and so to lean upon God, that if he fail thee thou sinkest. Confidence is the least, and yet the best we can render to the Lord, for hereby we acknowledge his sovereignty, and set the crown upon his head, as it were. See Judges 9:15 .
And lean not to thine own understanding.] Which, because men do, hence it is, many times, that the fairest blossoms of their endeavours wither, and the unprobablest things do come to pass. God loves to confute men in their confidences, as he did the Philistines in their champion Goliath. We must not, therefore, trust - no, not trust itself - but God, on whom it relies, who is therefore called our trust. They trust not God at all that do it not alone. He that stands with one foot on a rock, and another foot upon a quicksand, will sink and perish as certainly as he that stands with both feet on a quicksand. "Lord, lead me to a rock that is higher than I," saith David. Whither, when he was once got, then he sat and sang, "The Lord is my rock and my salvation." Psa 27:1 Surely, as one said of general councils, they seldom were successful, because men came with confidence, leaning to their own understanding, and seeking for victory rather than verity. So it holds as true in other like cases.