This book presents a theological and doctrinal interpretation of the book of Acts, focusing on an in-depth exploration of the theological meaning behind the events of early church history. It also highlights the Church teachings (doctrines) embedded in the Acts narrative. The author emphasizes the role of the Holy Spirit as the primary driving force in the expansion of the early church, often interpreting events as divine action to support the apostles' mission. The book systematically explains how the Gospel spread from Jerusalem to the Gentile world under the guidance of the Holy Spirit, highlighting the church's transition from a Jewish community to a universal church. It also covers the ministry of Peter (the early chapters) through Paul's missionary journeys, with an emphasis on themes such as martyrdom (witness), fellowship, and apostolic succession. This book is considered a valuable resource for those interested in the study of Catholic/Christian theology, church history, and the application of doctrine to biblical texts.