Adherence to the Sunnah
From: Usul al-Kafi
146 Prophet Muhammad (p): Every truth has a reality and every right deed has a light (noor) above it. You must follow what ever is relevant to the Noble Quran and reject that which is irrelevant to it.
147 Imam Jafar as-Sadiq (p) was asked about the different traditions related by those who are trustworthy and also by those who are not.
The Imam (p): Whenever a tradition comes to you which is supported by any verse from the Book of God, or by a saying of the Prophet Muhammad (p) then accept it. Otherwise accept only what comes to you through a trustworthy narrator.
148 Imam Jafar as-Sadiq (p): Every tradition should be referred to the Noble Quran and the traditions of the Prophet. The tradition that is not in agreement with the Holy Quran is useless.
149 Imam Jafar as-Sadiq (p): Any tradition which is not in agreement with the teachings of Noble Quran, is a fabrication.
150 Prophet Muhammad (p): O people, whatever sayings you come across attributed to me, are mine if they are in consonance with the Book of God. But if they are not in consonance, I have not said them.
151 Imam Jafar as-Sadiq (p): One who opposes the Book of God or the traditions established by Prophet Muhammad (p), becomes an infidel.
152 Imam Zainul Abideen (p): The deed as per the Sunnah, is considered to be the best deed in the sight of God, even if it may be of small degree.
153 A believer asked Imam Muhammad al-Baqir (p) a question and he replied.
The believer: But the other scholars of jurisprudence do not say that.
The Imam (p): It is a pity. Have you ever seen a scholar of jurisprudence? A scholar who is really a scholar of religious jurisprudence, is one who has forsaken the pleasures of the world, and who pays attention only to his life in the Hereafter, and who always adheres to the Sunnah of the Prophet Muhammad (p).
154 Prophet Muhammad (p): Words have no value unless acted upon, and words and deeds combined have no value without intention, and all three combined have no value if they are not consistent with the traditions.
155 Imam Jafar as-Sadiq (p): There is no one without excitement and calmness. One whose calmness directs towards Sunnah is rightly guided, and the one whose calmness directs towards unorthodoxy is mislead.
Imam Jafar as-Sadiq (p): Every one has excitement and calmness. One whose calmness directs them towards Sunnah (Tridition of the Prophet (p)) is rightly guided, and the one whose calmness directs them towards unorthodoxy is mislead.
156 Imam Ali (p): There are two kinds of Sunnah. The compulsory ones; acting on them is obligatory and ignoring them is like turning away from the right path. And those which are optional; acting on them are excellent but there is no sin in ignoring them.