Sunnah refers to that is authentically reported on the Prophet صلى الله عليه وسلم – Shaykh Al Albaani
An Important Note:
It is obvious that after all of this we must say: Indeed, the Sunnah that bears this importance in Legislation (i.e. making Islamic laws), only refers to the Sunnah that is authentically reported on the Prophet صلى الله عليه وسلم by way of the knowledge-based paths and authentic chains of narration, which are well known to the scholars of Hadeeth and Narrators. It does not refer to that which is contained within the various books of Tafseer and Fiqh, or the books on Targheeb and Tarheeb, or those of Raqaa’iq and Mawaa’idh, for indeed many of the weak, rejected and fabricated ahaadeeth can be found in them.
Some of these ahaadeeth, Islaam is completely free from, such as the hadeeth about Harut and Marut, and the story on the satanic verses (gharaneeq). I wrote a specific treatise refuting this narration, which has been published. I have referenced a score of them in my book, the collection: Silsilat-ul-Ahaadeeth ad-Da’eefah wal-Mawdoo’ah wa Atharuhaa as-Sayy fil-Ummah.” So far the number of ahaadeeth in them has reached close to four thousand. And they consist of ahaadeeth that are either weak or fabricated. Only five hundred ahaadeeth from these have been published so far! So it is an obligation upon the people of knowledge, particularly those that propagate their Fiqh and verdicts to the people, to not be overconfident in using the hadeeth as proof except after becoming sure about its authenticity. This is especially since the books of Fiqh that are commonly referenced today are filled with ahaadeeth that are weak, rejected and those that have no source to them, as is well known to the scholars.
I have commenced an important project in my opinion, which is beneficial for those who preoccupy themselves with Fiqh, which I call: “The Weak and Fabricated Ahaadeeth in the Major Fiqh Books.” By this I mean the following books:
1. Al-Hidaayah of Al-Margeenaani, regarding Hanafi Fiqh
2. Al-Mudawwanah of Ibn Al-Qaasim, regarding Maalikee Fiqh
3. Sharh-ul-Wajeez of Ar-Raafi’ee, regarding Shaafi’ee Fiqh
4. Al-Mughnee of Ibn Qudaamah, regarding Hanbalee Fiqh
5. Bidaayat-ul-Mujtahid of Ibn Rushd, on comparative Fiqh.
Unfortunately, however, I did not get the chance to complete it because the Kuwaiti magazine, Al-Wa’ee Al-Islaamee, that promised to publish it and that received it graciously after reviewing it, didn’t print it.
Since I missed that opportunity, then perhaps I will be granted the opportunity, Allaah willing, on another occasion to offer a specific knowledge-based course to my brothers that are studying Fiqh, which will assist them and which will facilitate for them the way towards knowing the grades of the Hadeeth, by returning them to the necessary sources of the books of Hadeeth. And which will explain their special and distinct characteristics, as well as what can be relied on from them. And Allaah, Most High, is the One who grants success.
 The book is called: “Nasab-ul-Majaaneeq fee Nasf Qissat-il-Gharaaneeq.” [Printed by Al-Maktab-ul- Islaamee]
 Now the number has passed five thousand ahaadeeth, may Allaah facilitate them to be printed soon