A.B. Simpson emphasizes the importance of trusting God not only for spiritual matters but also for our daily material needs. He points out that while it may be easy to claim faith in abstract spiritual concepts, true trust is tested in practical situations involving rent, food, and other necessities. Simpson argues that real faith is revealed when we face challenges that require tangible answers, and that our everyday needs serve as a litmus test for our reliance on God. He challenges listeners to examine whether they are wholly trusting God in all aspects of their lives.