He also confirmed to them - peace be upon him - that he had conveyed to them the message of his Lord in full, and whatever good there was but he had showed it to them, and whatever evil there was, but he had warned them about. In the statement of Abdullah bin ‘Amr he said: The Messenger of Allah - peace be upon him - said: (There was no Prophet that has gone before me but had the duty to designate to his nation to what he knew was good for them and warn them against what he knew was bad for them ...)(1).
The ultimate good which he committed to the nation and recommended was holding fast to the Book and the Sunnah, for there is therein guidance and salvation. He - peace be upon him - said: (I have left among you that which if you hold fast to, you will never go astray: the Book of Allah and the Sunnah of His Prophet, peace be upon him) (2).
The noble Companions have responded to this testament. They were the greatest of people in holding fast to the law (of Allah), and observing the provisions, because they perceived these meanings. They realized that religion is fulfilled and was not in need of additions, and that the Law has been shown up and became clear, and therefore was not in need for elucidation. The matter was rather in terms of compliance and following. They were such as Ibn Mas'ud - may Allah be pleased with him – described them (the best of this nation: the most righteous of hearts, the deepest of knowledge and the least in formality) (3).
People remained this way until the passions blew them away, the opinions manipulated them, the paths led them to deviation and the evil, which Allah warned from, occurred. The Almighty said: (As for those who divide their religion and break up into sects, you have no part in them in the least) (4).
Ibn Katheer said: (It seems that the verse is general concerning all those who parted with the religion of Allah and contravened him, for Allah sent His Messenger with Guidance and the Religion of Truth, to proclaim it over all religion, and His Law is one; no disagreement in it and no separation. Those who disagree in it (and they were into sects), ie: teams, such as religious sects and creeds – which are whims and delusions - Allah has exculpated His messenger from what they are into, and this verse such as the saying of the Almighty: (The same religion has He established for you as that which He enjoined on Noah – and that which We have sent by inspiration to you - and that which We enjoined on Abraham, Moses, and Jesus: Namely, that you should remain steadfast in religion, and make no divisions therein) the verse ...
This is the straight path, which the Apostles came with: from the worship of Allah alone with no partner and the adherence to the law of the late Prophet, and other than that is but delusions and ignorance, and opinions and whims, from which the Apostles are innocent) (5).
(1) Narrated by Muslim, the Book on Government, the chapter pertaining to keeping loyal to the pledge of oath to the successor in succession (1844).
(2) Narrated by Al Haakim, the Book of Science, the chapter pertaining to his Sermon - peace be upon him - in the Farewell Pilgrimage (318), and said: in its chain of narration is ‘Ikrimah and Bukhari remonstrated by it, and Ibn Abi Awys, and Muslim remonstrated by it, and all its narrators are agreed upon, and then said: He has got a witness from the statement of Abu Hurayrah, and documented in a previous instance, and Adh-Dhahabi agreed with him and said: it has an origin in the authentic.
(3) A part of a trailer narrated by Baghawi according to Ibn Mas'ud in the exegesis of the Sunnah (1, 214).
(4) Surah Al An’am, 159.
(5) ‘Umdatut-Tafseer (1, 845).