This book is inspired primarily by the desire to contribute to the work towards Christian Unity in the Philippines. It discusses matters between the Roman Catholic Church in the Philippines (RCCP) and the Iglesia Filipina Independiente (IFI) noting that the IFI separated from the Roman Catholic Church in the beginning of the twentieth century. Having compared the ecclesiologies of RCCP and IFI through Receptive Ecumenism, this work articulates the things that RCCP could learn from the IFI as a ‘Church of the Poor,’ notably in terms of theology, worship, spirituality, and discipline. Moreover, the process of receptive learning by the RCCP has led to the discovery and establishment of greater bonds of unity with the IFI, i.e., a more visible unity and a more profound understanding of the Church as koinonia.