Lack of unity among branches of the same religion, and splits into many denominations, are caused by schism and doctrinal controversy. No real advance towards unity can be made if cultural, social, political and psychological components of the religious life are not painstakingly analyzed and evaluated. Many unconscious and unavowed prejudices and false presuppositions are too often treated as essentially in harmony with sacred texts, rather than as the conditioning of a particular culture and society.
The history of divisions in the Christian church is to a large extent reflected in the history of political systems and concepts. Division is a universal reality. Although, in the light of religious apathy in Western industrialized countries, Christian Churches are attempting to eliminate some of their differences and to preserve a relevance to the modern age through their fundamental unity, interdenominational intolerance and prejudice still persist.
In the case of the Christian churches the deepest difference has many forms and deep roots. It exists among many other differences of emphasis within Christianity. Some are Catholic or Orthodox in clearly understood senses; some are Protestant after the great Reformation confessions; others stress the local congregation, the gathered community, and the idea of the free church. Some are deeply convinced that Catholic and Protestant (or Evangelical) can be held together within a single church. The clearest obstacle to manifestation of the churches' universality is their inability to understand the measure in which they already belong together in one body.
"Within our divided churches, there is much which we confess with penitence, for it is in our estrangement from God that all our sin has its origin. It is because of this that the evils of the world have so deeply penetrated our churches, so that amongst us too there are are worldly standards of success, class division, economic rivalry, a secular mind. Even where there are no divisions of theology, language or liturgy, there exist churches segregated by race and colour, a scandal within the Body of Christ".
The basic division amongst the Christian churches is epitomized by the Catholic-Protestant split. "From each side of that division we see the Christian faith and life as a self-consistent whole, but our two conceptions of the whole are inconsistent with each other". "We differ in our understanding of the relation of our unity in Christ to the visible holy, Catholic and Apostolic Church. We are agreed that there are not two Churches, one visible and the other invisible, but one Church which must find visible expression on earth, but we differ in our belief as to whether certain doctrinal, sacramental and ministerial forms are of the essence of the Church itself. In consequence, we differ in our understanding of the character of the unity of the Church for which we hope, though none of us looks forward to an institution with a rigid uniformity of governmental structure".