Are you interested in research on God? Do you know who is God? Do you know the useless God? If the answer is "YES", this book is for you.This book is an original retelling of the ideas mainly elaborated in prison, and of its greatest exponent of these, the poem Christians and Non-Christians. Going beyond the already discussed interpretations, the book is a new focus on who God is and the faith required in his recognition. A silent hymn to the usefulness of uselessness. To the unnecessary necessary God.Contents- Introduction- Bonhoeffer and the Useless God- The needed need- God's disinterested experience- A useful distinction- The most useful is useless- Who is God?- A trajectory of thought- The poem- People go to God in their uselessness- Usefulness is the root of all evils- An exemplary case- People go to God in His uselessness- The last- The Needed in Need- Hidden infinite- The ultimate honesty- Who is the God of the Bible?- What is love?- Love-friendship- The unneeded needed- God seeks all people in their uselessness- Conclusion