What does Proverbs 16:1 mean?

A person can draw up plans the way a military officer arranges soldiers in formation. However, the outcome of those plans is beyond human efforts. It ultimately depends upon the Lord. When someone devotes their heart, mind, soul, and strength to God (Deuteronomy 6:5; Mark 12:30), God will guide that person's speech and conduct (Matthew 10:19–20). Of course, all persons are free to think what they will, but the future is ultimately in the Lord's hands.

The apostle James counsels us to seek the Lord's will before drawing up our plans. In James 4:13–14 he writes: "Come now, you who say, 'Today or tomorrow we will go into such and such a town and spend a year there and trade and make a profit'—yet you do not know what tomorrow will bring. What is your life? For you are a mist that appears for a little time and then vanishes." Instead of arrogantly assuming that our plans are invincible, or absolute, we ought to follow the counsel James gives next. He says, "Instead you ought to say, 'If the Lord wills, we will live and do this or that.'" (James 4:15)

That doesn't mean it's unwise to plan, at all. It simply means that proper planning includes acknowledging God's sovereign will and our limitations. That even includes the next day's events; we can't be absolutely certain about what will happen then. Proverbs 27:1 tells us, "Do not boast about tomorrow, for you do not know what a day may bring." A similar sentiment is offered in verse 9 (Proverbs 16:9).