In Islam the Law-giver is Allah Alone. Notwithstanding, the Qur'an is replete with principles that establish the authority of the holy Prophet (Sallallahu Alayhi Wasallam) as a legislator or a law-maker. Some of the Qur'anic ayat in this respect are reproduced below:
1. "To-day this mercy is for those who follow the Ummi Prophet, whom they find mentioned in the Torah and the Gospel with them. He enjoins upon them what is good and forbids them what is evil. He makes the clean things lawful to them and prohibits all corrupt things, and removes from them their burdens and the shackles that were upon them. So those who believe in him and assist him, and succour him and follow the Light which has been sent down with him, it is they who shall prosper." (7:156-157) (Emphasis added).
The emphasized words in the quoted ayah signify that one of the functions of the holy Prophet is "to make good things lawful and impure things unlawful." What does that imply? That is, the enforcing of new laws regarding the permissibility or prohibition of things is one of the sole responsibilities of the holy Prophet. This function of prescribing new religious laws and rules is attributed here to the holy Prophet who did this job by further explaining and making the law by his Sunnah.
The ayah also emphasizes "to believe" in the holy Prophet. In the present context, it clearly means to believe in all his functions mentioned in the ayah including to make something "lawful" or "unlawful."
The ayah, moreover, directs the Muslims to follow 'the light' that has been sent down with him. What is that light? One must reflect why instead of "following the Qur'an" "following the light" has been ordered. Down the ages the mainstream scholars of the Qur'an and the hadith have been understanding that 'the light' refers to all the imperatives sent down to the holy Prophet either through the Qur'anic revelation or through the unrecited revelation, reflecting in his own orders and acts which again refers to nothing but the hadith and the sunnah.
From whatever angle one looks at the ayah it is a clear proof of the fact that the holy Prophet had an authority based, of course, on the unrecited revelation, to make new laws in addition to those mentioned in the Holy Qur'ân.
Allah says in the Qur'an:
2. Fight those who do not believe in Allah and the Hereafter and do not hold unlawful what Allah and His Messenger have made unlawful. (9:29)
The bold words signify that it is necessary to "hold unlawful what Allah and His Messenger made unlawful," and that the authority making something unlawful is not restricted to Allah Almighty. The Holy Prophet can also, by the will of Allâh, exercise this authority. But one thing must be borne in mind here. That is the delicate difference between the authority of Allah and the authority of the Messenger. While the authority of Allah is wholly independent, intrinsic and self-existent, the authority of the holy Prophet is derived from and dependent on the revelation from Allah. Yet, the fact remains that the holy Prophet has this authority and it is necessary for believers to submit to it along with their submission to the authority of Allah.
The Holy Qur'an says:
3. No believer, neither man nor woman, has a right, when Allâh and His Messenger decide a matter, to have a choice in their matter in issue. And whoever disobeys Allâh and His Messenger has gone astray into manifest error. (33:36)
Here, the decisions of Allah and the Messenger both have been declared binding on the believers.
'It is worth mentioning that the word "and" occurring between "Allah" and "His Messenger" carries both conjunctive and disjunctive meanings. It cannot be held to give conjunctive sense only, because in that case it will exclude the decision of Allah unless it is combined with the decision of the messenger- a construction too fallacious to be imagined in the divine expression. The only reasonable construction, therefore, is to take the word "and" in both conjunctive and disjunctive meanings. The sense is that whenever Allah or His Messenger, any one or both of them, decide a matter, the believers have no choice except to submit to their decisions.'
It is therefore, very much clear that the holy Prophet has the legal authority to deliver decisions in the collective and individual affairs of the believers who are bound to surrender to those decisions. And that is the legal status of his sunnah in Islam as the second source of the Shari'ah after the Qur'an.
The Qur'an again says:
4. Whatever the Messenger gives you, take it; and whatever he forbids you, refrain from it. (59:7)
'Although the context of this verse relates to the distribution of the spoils of war, yet it is the well-known principle of the interpretation of the Qur'an that, notwithstanding the particular event in which a verse is revealed, if the words used are general, they are to be construed in their general sense; they cannot be restricted to that particular event.
According to this undisputed principle, the ayah gives a general rule about the holy Prophet that whatever order he gives is binding on the believers and whatever thing he forbids stands prohibited for them. The Qur'ân thus has conferred a legal authority to the holy Prophet to give orders, to make laws and to enforce prohibitions.
It will be interesting here to cite a wise reply of 'Abdullâh ibn Mas'ud (radi Allahu 'anhu), one of the great Sahabah of the holy Prophet who knew the Qur'an the most. A came to him and said, "I have come to know that you hold such and such things as prohibited and you also claim that the prohibition is in the Qur'an. I have gone through the whole Book of Allah, but never found any such prohibition in it."
'Abdullah ibn Mas'ud replied, "Had you read the Book you would have found it. Allâh Almighty says: "Whatever the Messenger gives you, take it; and whatever he forbids you, refrain from it." (Ibn Majah)
By this answer 'Abdullah ibn Mas'ûd pointed out that according to the quoted ayah whatever order the holy Prophet gives is necessarily a revealed order given to him by Allah through the unrecited revelation. Therefore, all the orders of the holy Prophet form part of the revelation.
The Qur'an says:
5. But no, by your Lord, they shall not be (deemed to be) believers unless they accept you as judge in their disputes, then find in their hearts no adverse feeling against what you decided, but surrender to it in complete submission. (4:65)
'The authority of the holy Prophet established in this ayah seems apparently to be an authority to adjudicate in the disputes brought before him. But after due consideration in the construction used here, this authority appears to be more than that of a judge. A judge, no doubt, has an authority to deliver his judgments, but the submission to his judgments is not a condition for being a Muslim. If somebody does not accept the judgment of a duly authorized judge, it can be a gross misconduct on his part, and a great sin, for which he may be punished, but he cannot be excluded from the pale of Islam on this score alone. He cannot be held as disbeliever.'
'On the contrary, the verse vehemently insists that the person who does not accept the verdicts of the holy Prophet cannot be held to be a believer. This forceful assertion indicates that the authority of the holy Prophet is not merely that of a customary judge. The denial of his judgments amounts to disbelief. It implies that the verdicts of the holy Prophet referred to here are not the normal verdicts given in the process of a trial. They are the laws laid down by him on the basis of the revelation, recited or unrecited, that he receives from Allâh.
Looked at from this point of view, this verse gives the Holy Prophet (Sallallaho Alaihe Wassallam) not only the authority of a judge, but also confers upon him the authority to make laws, as binding on the Muslims as the divine laws.
The Qur'an says:
They say, "we believe in Allâh and the Messenger, and we obey." Then, after that, a group of them turn away. And they are not believers. And when they are called to Allâh and His Messenger that he may judge between them, suddenly a group of them turn back. But if they had a right, they come to him submissively! Is it that there is sickness in their hearts? Or are they in doubt? Or do they fear that Allâh may be unjust towards them, and His Messenger? Nay, but they are the unjust. All that the believers say when they are called to Allâh and His Messenger that he (the Messenger) may judge between them, is that they say, "We hear and we obey." And they are those who acquire success. And whoever obeys Allâh and His Messenger and fears Allâh and observes His Awe, such are those who are the winners. (24:47-52)
The injunction is the same i.e., those who do not turn towards the holy Prophet in their disputes inspite of being called to him cannot, according to the Qur'an, be treated as believers. 'It carries the same principle as mentioned in the preceding verse: It is the basic ingredient of the belief in Allâh and His Messenger that the authority of the Messenger should be accepted whole-heartedly. He must be consulted in disputes and obeyed. His verdicts must be followed in total submission, and the laws enunciated by him must be held as binding.'