The aim of this book is as modest as it is ambitious. It sees itself booth as a manual of the history of the church, and as an essay. The manual is of service to the students of theology and at the same time lays open to them the problems linked to the subject of their studies. The first and foremost aim of the book however is to offer an overall view of the 2000 years of the history of the Catholic Church and the other Christian denominations. It is the history of hights and failures, of incidents an devents as reactions to the different challanges to the faith and the church. It is the story of breakdowns leading to new starts, of conversions and continous building up, and this gives the story ist particular rhythm, against which the believer always tries to separate the wheat from the chaff, as a means to discover the finger of God, who writes in the sand of history. From that point of view the book is an essay in the true sense of the word.