All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
The statements from the companions and the Tabi’is (the generation that followed that of the Companions) that were recorded in the books of jurisprudence are subject to being judged regarding whether they are authentic or inauthentic in the same way as the Hadiths narrated from the Prophet Some of them are authentic, and some are not. Additionally, the seeker of knowledge and those who are of lesser ranking, should seek help from the statements of the reviewers [prominent scholars who review the Ahadeeth and their chain of narrators] in ruling whether the statements of the Companions are authentic or weak.
What strengthens the possibility of the authenticity of a statement of Companions or others is when it is used as evidence by one of the great reviewers among the scholars, such as Ibn Abd al-Barr, an-Nawawi, Ibn Qudamah, and Sheikh al-Islam Ibn Taymiyyah, may Allaah have mercy upon all of them.
The conditions for accepting the statements of righteous predecessors from among the Companions and the Tabi’is, in general, are less than the conditions for accepting the Hadith attributed to the Prophet, sallallaahu alayhi wa sallm.
Scholars scrutinize and carefully examine the Hadiths of the Prophet, sallallaahu alayhi wa sallm, regarding Islamic rulings more than they do for others.
Allah knows best.