What would it take for the Church to become one? In Father, May They Be One, Dr Enemona Emmanuel Adaji takes the prayer of Jesus in John 17 as his starting point and asks why the Church, two thousand years later, remains so deeply divided. With the rigour of a scientist and the heart of a believer, he examines the theological, historical, and human roots of Christian disunity, and charts a compelling path toward the unity Christ prayed for. Drawing on scripture, personal experience of Catholic and Pentecostal traditions, and a lifelong pursuit of God, this book offers both an honest reckoning with division and a hopeful vision for a Church that reflects the oneness of the Father, Son, and Holy Spirit. This is not an academic treatise. It is a call, a call to the divided Church to take seriously the prayer of Jesus, and to ask what we are willing to lay down so that the world might believe.