‘David went out whithersoever Saul sent him, and behaved himself wisely.’ He would act as a servant loyal to the king; he would await God's timing with regard to the change of rule, however that might be accomplished.
To walk circumspectly is a good definition of Christian wisdom. David never underestimated the task, as we might be inclined to do. When we are going to preach or teach Sunday School, or visit, or witness, or shepherd, or help, or counsel others – whatever we do – never underestimate the task. To live as a witness week after week, year after year in an office setting is not easy: never underestimate the task. Never overestimate yourself. These are really components of wisdom. Take it carefully. Consider the implications of everything you do, how it would affect other people. Behave wisely. Put a careful check on pride. You are going to have many successes, many advances, and immediately you are likely to succumb to the temptation to be proud. Don't do the things which cause pride to sore, living expensively, over-pampering yourself. You see it among people worldwide, and Christian casualties in the pilgrimage of the Christian life. People aim too high, and it goes to their heads, and affects their whole deportment and spirit. David behaved himself wisely. He put a check on his habits and his possessions. Nobody could say, ‘Look at that; he thinks he is the crown prince; look at the way he leaves the royal court. Now he has got himself a whole set of stallions and an entourage. It's gone to his head. Who does he think he is?’ They couldn't speak like that of David. He didn't take advantage of his privileges and his positions. He behaved himself circumspectly, wisely.
The word translated ‘behaved wisely’ is rendered ‘was successful’ by some versions. The lexicons say that it can have this meaning in the hiphil form. It occurs four times in this chapter (verses 5, 14, 15, and 30), and in the first three occurrences the form is hiphil, and to say that David was successful gives a reasonable sense, and could explain why he was accepted in the sight of the people. However the last occurrence in verse 30 is in the qal form which more often means to be prudent, to behave wisely. Since all the uses of the word must in context have the same meaning, it seems better to go with the KJV rendering ‘behaved wisely’. This gives a stronger reason for the acceptance of the people than simply being successful, and the comparative form in verse 30 – ‘… than all the servants of Saul’ – makes better sense with the idea of behaving wisely than it does with the idea of being successful.