The book The Gospel of the Kingdom: The Good News That Must Be Preached to All Nations by Elvis Lucas presents "The Gospel of the Kingdom" as the central and authentic message of Christianity, distinct from modern, individualized interpretations. It emphasizes that Jesus's core mission and the apostles' proclamation revolved around God's earthly kingdom, which will be established at Christ's second coming after the worldwide dissemination of this gospel. The text explores the Abrahamic and Davidic covenants as foundational to this earthly kingdom, highlighting its governmental nature and the restoration of creation. It urges believers to embrace kingdom citizenship now, living according to kingdom values and actively participating in the Great Commission to hasten the kingdom's full establishment.