Allah (SWT) commands Muslims in the Noble Quran many times to "Obey Allah and His Messenger." Therefore there has never been any doubt amongst the scholars of Islam that the Quran could not be properly understood without the Hadith; the teachings and sayings of the Prophet Muhammad (peace be upon him).

Like the Qur'an, the preservation of the traditions and sayings of the Prophet Muhammad [pbuh], the hadith, for fourteen centuries is another unsung miracle of Islam. It is important to recognize the long journey the hadith of the Blessed Prophet [pbuh] have made through the passage of time and how they have been protected against the perverting hands of distorters, corrupters, and mistake prone narrators.

How were the hadith preserved throughout history?
How did scholars ensure that the hadith used for establishing shariah are authentic?
Who were the great scholars who devoted their lives to the preservation of hadith?
In this short treatise, the author, Shaikh Ibrahim Madani, has simplified much of the information found only in the larger texts on the science of hadith. In addition, he highlights the authority of hadith in Islam and how they were preserved. This book is an excellent start for those who wish to gain a basic understanding of this subject, but cannot invest the time or means to do so. - from Amzon