Introduction: The Obligation of Knowing Allah, Islam, and the Prophet

Imam Muhammad ibn Abdul Wahhab opens this foundational text with a matter of supreme urgency: that Allah has made it obligatory upon every Muslim — man and woman — to know three things with certainty. These are knowledge of one's Lord (Allah), knowledge of one's religion (Islam), and knowledge of one's Prophet (Muhammad, peace be upon him). This is not an optional intellectual exercise but a religious duty whose neglect carries serious consequence.

The author begins by invoking the mercy and blessings of Allah and then establishes the framework of the entire treatise. He draws attention to the fact that every Muslim will be asked about these three things in the grave. The angels Munkar and Nakir will question the deceased: "Who is your Lord? What is your religion? Who is your prophet?" The ability to answer these questions with firm conviction — rooted in knowledge, not mere habit or cultural identity — is the fruit of proper learning and sincere faith.

Ibn Abdul Wahhab grounds this obligation in the Quran and Sunnah. Allah says: "So know that there is no deity except Allah" (Muhammad, 47:19). This verse uses the imperative "know" (fa'lam), making knowledge of tawhid a command, not a suggestion. Similarly, the Prophet, peace be upon him, said: "Seeking knowledge is an obligation upon every Muslim" (Ibn Majah). The scholars of Islam have understood from such texts that the most obligatory knowledge is knowledge of the fundamentals of the faith.

The introduction also carries a profound pastoral concern. The author was writing in a time when widespread ignorance had crept into Muslim communities, and practices inconsistent with pure tawhid had become normalized. His goal was not to create a scholarly elite but to bring every Muslim back to the basics — the three questions that every soul, educated or not, will face.

The author also briefly introduces the concept of evidence (dalil). True knowledge in Islam is not based on blind tradition or cultural inheritance. It must be grounded in proofs from the Quran and authentic Sunnah. Throughout the treatise, Ibn Abdul Wahhab consistently pairs each principle with its textual evidence, training the reader to think in terms of "What is the proof?" This is a hallmark of the Salafi methodology he inherited from the classical scholars.

Finally, the introduction sets the tone of the book: accessible, direct, and built for the common Muslim. Unlike dense theological treatises aimed at specialists, Al-Usul ath-Thalathah is designed to be memorized and understood by ordinary believers. Its brevity is intentional. The author wanted every Muslim household to have these principles internalized, so that when the grave closes and the angels ask, the believer answers with clarity, conviction, and the light of knowledge rather than the darkness of ignorance.