There is a tradition of Muslim Open Letters to political and religious leaders in the non-Muslim world. This page has the purpose to collect links to various letters as well as discussions of and responses to those letters.
This open letter was written by 138 Muslim scholars addressing all leaders of Christianity. It resulted in a large number of responses and the page linked here provides an overview on various responses, as well as discussions of these responses.
The tradition of writing open letters as means to invite others to Islam goes back to Muhammad himself. His letters are important background information to understand the letters we are confronted with today.
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