Here you can find texts on the issues related the the distinction between the Sunnah and the bida’ (innovation) and between the people of the Sunnah and the people of bida’. The Salaf have laid down firm principles and explained the rules of these issues very clearly in order to remove the confusion of the confused, and the doubt of the arrogant.
Usul As-Sunnah – by Imam Ahmad ibn Hanbal
Here you can find and download texts that are related to the issue of judging upon the apparent, and refutation of the modern time Khawarij who insists on their hideous bid’ah of declaring anyone a disbeliever until they test them in their beliefs, even if they ascribe to Islam, say La ilaha illa Allah and pray the the prayer of Muhammad (sallallahu ‘alayhi wa sallam).
Here you can find ebooks and articles about the meaning of La ilaha illa Allah, and what it contains of issues such as: Al-Kufr bit-Taghut, declaring takfir upon the mushrikun, the pillars and conditions of Tawhid and more.
For a summarized overview of important issues on Tawhid refer to the book “An introduction to Tawhid and Sunnah”.
UPDATED!! Some issues regarding takfir
Mufid Al-Mustafid fi Kufr Tarik At-Tawhid – by Muhammad ibn Abdul-Wahhab
The Six Principles – by Muhammad ibn Abdul-Wahhab
The Four Principles – by Muhammad ibn Abdul-Wahhab
Explanation of six places in the Sirah – by Muhammad ibn Abdul-Wahhab
Takfir upon the mushrikun and its relation to Kufr bit-Taghut – by Ahmad ibn ‘Umar Al-HazimiMore texts
Here you can find articles about the consequences of sinning and disobedience towards Allah the Exalted, and some of the traps that the Shaytan may be able to lure the Muslim into without him being aware of this. All in the light of the Quran and Sunnah.