Authentication of Hadees

Authentication of Hadees is not only based on the Chain/authenticity of Narrations (Sanad) but also on the content. Infact the content is what is finally to be looked upon is deciding whether to take the Hadees or Not.

See the below 2 narrations:

1) Tafseer Al Ayyashi - Chapter on the abandonment of Hadees that is contradictory to the Quran
 

ـ عن محمد بن مسلم قال: قال ابوعبدالله (عليه السلام): يا محمد ما جائك في رواية من بر أو فاجر يوافق القرآن فخذ به، وما جائك في رواية من بر او فاجر يخالف القرآن فلا تأخذ به

From Muhammad b. Muslim. He said: Abu `Abdillah عليه السلام said: O Muhammad, whatever comes to you in a narration from a righteous person or an immoral person that agrees with the Quran, then take hold of it. And whatever comes to in a narration from a righteous person or an immoral person that contradicts the Quran, then do not take hold of it.

See more here: http://www.tashayyu.org/hadiths/quran/abandoning-narrations-that-are-contrary-to-the-quran

2) Al Kafi : The Book on Virtue of Knowledge : H 197, Ch. 22, h2

Muhammad ibn Yahya has narrated from ‘Abd Allah ibn Muhammad from Ali ibn al-Hakam from Aban ibn ‘Uthman from 'Abd Allah ibn abu Ya‘fur who has said the following.

"In a meeting where ibn abu Ya‘fur was also present I asked Imam abu ‘Abd Allah (DivineSupremeCovenantBody) about the differences in Hadith which is narrated from people whom we trust and yet from other people we do not trust." The Imam replied, "If you come across a Hadith and you find evidence in the Holy Quran to support it or in Hadith of the Holy Prophet (you may follow it), otherwise, you follow the one that has come to you through the trustworthy narrator."

3) Rejaal al-Kashi, p.195

Imam Sadiq (a.s) concerning al-Moghira Ibn Sa`eed said: "Verily, al-Moghira Ibn Sa`eed interpolated in the Hadith books of the companions of my father. He added things that my father had not said. Thus, fear Allah and do not accept anything (claimed to be) from us that contradicts the Words of our Lord and the Tradition of our Prophet Muhammad (P)."

4) Rejaal al-Kashi, p.195

Younus Ibn Abdul-Rahman said: “I met many people in Iraq who had met Imam Baqir and Imam Sadiq (peace be upon them). I heard their narrations and copied their books. Then when I met Imam Redha (a.s) I presented them to him. He denied many of those narrations and said: ‘Surely, Abul-Khattab fabricated in the name of Imam Sadiq (a.s). May the curse of Allah be upon Abul-Khattab and his followers who interpolated these narrations to this day in the books of the companions of Imam Sadiq (a.s). Do not accept anything (claimed to be) from us against the Quran.’"

The above Hadees are in conformity with the following verse of the Holy Quran which is used as a supporting argument for Ilm Ar Rijal according to which we cant just reject a Hadees because of lack of trustworthiness of the narrator:

Quran; Sura 49, Verse 5:

يَا أَيُّهَا الَّذِينَ آمَنُوا إِنْ جَاءَكُمْ فَاسِقٌ بِنَبَإٍ فَتَبَيَّنُوا أَنْ تُصِيبُوا قَوْمًا بِجَهَالَةٍ فَتُصْبِحُوا عَلَىٰ مَا فَعَلْتُمْ نَادِمِينَ

"O ye who believe! If a wicked person comes to you with any news, ascertain the truth, lest ye harm people unwittingly, and afterwards become full of repentance for what ye have done."

Hence as per the above verse we are to check for certinity of a Hadees even if the narrator is not trustworthy and cannot just brush aside the Hadees because of the lack of trustworthiness of the narrator.