Sahaba

From Anas (raa), he was asked (is there any one among the companions of Muhammad left after u), he (raa) said (some beduins remained who saw him (saaw), but the ones whom accompanied him and invaded with him no).  The hadith is narrated by Ibn Saad, Ibn Al Salah said (its isnad is good), and al sayooti said (bi'isnad hasan). On this meaning, the majority of the scholars of usuls went that the person will not be a sahabi unless he lives with the messenger (saaw) for enough period of time. On the other hand, the opinion of the majority of the scholars of the hadith that the one who saw him (saaw) and believed in him , he is a companion. Then these  differed will a person who saw him, then became a muslim after his death, a sahabi? Then some of them said even if he saw him from a far distance, he is a sahabi. And comes in the definition of the muhaditheen for the sahabi , the jin because the they had filled the requirements. And the basis of the definition is the word (sahabi) in arabic language, since the shairah did not put a special meaning for it, then we have to go with the linguistic meaning for the word. And the arabic language dictates in the urf (use)that enough period of friedship needed for companionship, and there is no consideration in this regard for the later scholars whom tried to revolve around and claim that companionship does not need a period of mulazama (close friendship). 

If u see this, then the haqq is with the scholars of usuls.  and it was narrated from Saaed Ibn Al Mussaiab (the imam of the followers) he said (we used not to consider a person from the companions except if he lived with the messenger for one or two year OR he invaded with him one or two battles). And it was mentioned that some of the tabieen used to narrate from some people who saw the messenger (saaw),  then they they were not from the sahaba. And the goal of the scholars of the hadith is that they want to add the virtue of the companionship to any one who saw the honorable face of the messenger (saaw), so that a group of people whom the messenger (saaw) witnessed for them with the virtue will not go out from companionship like jareer Ibn Abdillah al bujli and others.

On the other hand, the usuli scholar he is the one who establishes rules and fundemantals of the deen, since the sahaba are the ones who gave us the shariah, and transmitted the quraan and alone their ijmaa is definite. The imam said, the messenger (saaw( said (allah had chosen my companions over all people except the           prophets). Allah swt said (the early ones of muhajiroun and ansar...allah is pleased with them and they are pleased with allah) and this exclusive purification does not apply excxept to the sahaba. The imam said (and his words are taken from abu zarah) "and the sahaba are better than all others, and they are better than all the ones will come. This is because the deen is haqq and allah is haqq, and those who gave us this deen are the sahaba. And those who slander the sahaba, they are slandering our witnesses). (may be i misused the words).