“Who is the man who fears the Lord? Him will he instruct in the way that he should choose.” -Psalm 25:12
The line is framed in such a way as to raise some doubt or concern about the prevalence of such a man. Men who fear the Lord are not easily found. But if a man who fears the Lord can be found, the psalmist is sure the Lord will instruct him in the way he should go. That does not mean this man could not sin or make a mistake in judgment, but that God, by the illumination of the Holy Spirit, takes such a one under his direction and makes known to him his duty.
Solomon seems to have meant something similar when he said, “Trust in the Lord with all your heart, and do not lean on your own understanding. In all your ways acknowledge him, and he will make straight your paths.” -Proverbs 3:5–6