In this sermon, the speaker reflects on the need for Christians to have a mature understanding of the spiritual battle they face. He uses the example of a young man in military training to illustrate the idea that sometimes we may not feel like we need the challenges and hardships in our lives, but they are necessary for our growth. The speaker then transitions to a biblical story from 2 Samuel, where a fierce battle takes place between the armies of Ishvosheth and David. He emphasizes the vividness of the scene and highlights the importance of commitment in winning a war. The sermon concludes with a reference to Winston Churchill's speeches during wartime, emphasizing the need for commitment in achieving victory.