The apostle Paul said that we are to "cleanse ourselves from all filthiness of the flesh and spirit" (2 Corinthians 7:1). Even though it may seem to people around us that we are living a clean, moral life, in our spirit we may be harboring an attitude that displeases the Lord. Because sins of the spirit are unseen, hidden in the heart, we tend to ignore them until they lead to some outward behavior that reveals their presence.

King David's life illustrates these two aspects of sin. His lust for Bathsheba led to adultery and murder (2 Samuel 11-12; Ps. 32:5), and brought great pain to his own life and reproach to the nation of Israel. Then, late in his life, he succumbed to Satan's prompting to take a census (1 Chronicles 21:1-6). This seemingly innocent act displeased God (vv.7-8) because David was taking pride in his military might. There seems to have been a subtle shift from completely relying on God, who had often miraculously delivered him, to trusting in his own power and strength.

On the outside, it may appear to others that we are winning the battle against sin. But we must stay alert to the sins of the spirit, especially pride. They can cause us to stumble and fall, even at the end of life's journey.  — Dennis J. De Haan