The Kingdom That Must Be Built by Walter J. Carey is a profound exploration of faith and the Christian journey towards building God's Kingdom on earth. The book delves into the significance of having a right faith as the foundation for action emphasizing the Creed as a guide for facing challenges and reforming the world with confidence. It highlights the Christian's role in removing hindrances establishing righteousness and finding joy in co-operating with God. Through reflections on reward service and the ultimate purpose of building Christ's Kingdom the book inspires readers to live a purposeful and faithful life.