David Wilkerson emphasizes the spiritual warfare depicted in the story of Queen Esther, where Esther's bravery and faith led to the salvation of her people from Haman's evil plot. The sermon illustrates how trials and battles not only strengthen our faith but also yield spiritual riches that are more precious than gold. Wilkerson highlights that through Christ's victory at Calvary, believers are endowed with grace, mercy, and the resources needed to maintain their spiritual lives. He encourages the congregation to tap into the Holy Spirit's treasury to sustain their faith and character amidst conflicts. Ultimately, the message conveys that there is value in every battle we face, as it contributes to our growth and the glory of God.