A book in German in which the author shows the fundamentals principles that a Muslim has to know about Allah, Islam, and the Prophet Muhammad. He also shows the types of worship that Allah commanded in a brief and easy explanation.
A book in German confirms that tolerance has a vital role and supreme prestige in all aspects of Islam, for Islam is a divine revelation to people of different feelings and skills. Allah said, "... and He has not laid upon you in religion any hardship."