This work presents the essential details of purification and prayer which should be known by every serious Muslim. Avoiding hypothetical and unlikely cases, it deals with issues that are likely to arise in the life of the average urban Muslim. Among the main features of this book is that it balances legal issues with healthy doses of spirituality and addresses contemporary issues such as wearing nail polish, holding a digital Qur'an without purifying, using hormones to delay menstruation, praying on an airplane, etc. Guide of the Believer is like a modern instruction manual which can be read independently or studied in detail with an expert in the field.