The book "The Harp of God: Convincing Evidence That Millions Now Living Will Never Die" was written by the author Joseph Franklin Rutherford, who was one of the prominent figures in the religious movement of Jehovah's Witnesses. In this book, the author tries to give convincing evidence and arguments in support of his idea that the apocalypse and the coming of the Kingdom of God are coming, and that it will be witnessed by people living now. Rutherford examines various prophecies from the Bible, presenting their interpretation and substantiating his claims. Through its combination of religious predictions and scientific arguments, this book has become an essential work for adherents of the religious movement and anyone interested in apocalyptic theology.