How do we know the importance of spiritual knowledge?

In Luke 8:16, our Lord illustrates that spiritual knowledge is like a candle that should not be covered or hidden, but rather placed on a candlestick to illuminate the darkness. This metaphor highlights the duty of every believer to utilize their understanding of the Gospel actively and visibly in their lives. It is not enough to possess spiritual truths; believers are called to practice and share their faith with others. By recognizing that many are without hope, the urgency to spread this light becomes paramount. This duty speaks to the responsibility every Christian has in testifying their faith and joyfully drawing others to the light of Christ. A Christian who is content to keep this knowledge to themselves is acting in spiritual selfishness.