Proverbs 25:28 Whoever has no rule over his own spirit is like a city broken down, without walls.
A city without walls in ancient days was vulnerable to its enemies who could assault it without obstacles. Well-built walls around a city forced its enemies to attack in the open through hails o arrows and rocks from above, making the city a safe refuge, all things being equal.
I have known many disciplined individuals. Two of my friends in college slept with the window open in the winter and arose early, even on weekends, just to discipline themselves. Another studied an entire semester with little rest. On weekends he studied continuously, never leaving the room even for meals.
We could mention athletes who were disciplined, as well as teachers, farmers and other workers who stood out for their disciplined life and great accomplishments. Perhaps most honorable of all in the secular world are the servicemen who have endured the worst of conditions, sometimes without food or rest and facing a stronger enemy, all for the sake of the citizenry they served or that of another country.
These are noble efforts. But if such discipline does not address the spiritual and moral realm, if it is all spent for self or some un-Christian cause, it will be in vain. Even thieves can be discipline. We do well to imitate those outstanding Christians who were or are disciplined within and without.
But I discipline my body and bring it into subjection, lest, when I have preached to others, I myself should become disqualified. (1 Cor 9:27)
We cannot succeed in the Christian life without self-control over our body and our passions. If we are inclined to self-indulgence in any aspect of our life, we are vulnerable to forces of evil like an un-walled city. Peter said:
Be sober, be vigilant; because your adversary the devil walks about like a roaring lion, seeking whom he may devour. (1 Peter 5:8)
Is there an area of your life that you have not been able to tame for the sake of Christ and His kingdom? If so, commit today to rule over it with discipline and God's help.