Matthew Henry's Concise Commentary
3:1-6 In the way of believing obedience to God's commandments health and peace may commonly be enjoyed; and though our days may not be long upon earth, we shall live for ever in heaven. Let not mercy and truth forsake thee; God's mercy in promising, and his truth in performing: live up to them, keep up thine interest in them, and take the comfort of them. We must trust in the Lord with all our hearts, believing he is able and wise to do what is best.
Those who know themselves, find their own understandings a broken reed, which, if they lean upon, will fail. Do not design any thing but what is lawful, and beg God to direct thee in every case, though it may seem quite plain. In all our ways that prove pleasant, in which we gain our point, we must acknowledge God with thankfulness. In all our ways that prove uncomfortable, and that are hedged up with thorns, we must acknowledge him with submission. It is promised, He shall direct thy paths; so that thy way shall be safe and good, and happy at last.
Trust in the LORD with all your heart and lean not on your own understanding;