Those who do not Judge in the light of Quran, are KAFIROON


"It was We who revealed the law (to Moses): therein was guidance and light. By its standard have been judged the Jews, by the prophets who bowed (as in Islam) to Allah's will, by the rabbis and the doctors of law: for to them was entrusted the protection of Allah's book, and they were witnesses thereto: therefore fear not men, but fear me, and sell not my signs for a miserable price. If any do fail to judge by (the light of) what Allah hath revealed, they are (no better than) Unbelievers/KAFIROON [5/44]. "

Those who do not judge in the light of Quran, are ZALIMOON


"We ordained therein for them: "Life for life, eye for eye, nose or nose, ear for ear, tooth for tooth, and wounds equal for equal." But if any one remits the retaliation by way of charity, it is an act of atonement for himself. And if any fail to judge by (the light of) what Allah hath revealed, they are (No better than) wrong-doers/ZALIMOON [5/45]. "

Those who do not judge in the light of Quran, are FISIQOON


"Let the people of the Gospel judge by what Allah hath revealed therein. If any do fail to judge by (the light of) what Allah hath revealed, they are (no better than) those who rebel/FASIQOON. 5/47"

Muhammad (p.b.u.h), himself was ordered to judge in the light of Quran


"To thee We sent the Scripture in truth, confirming the scripture that came before it, and guarding it in safety: so judge between them by what Allah hath revealed, and follow not their vain desires, diverging from the Truth that hath come to thee. To each among you have we prescribed a law and an open way. If Allah had so willed, He would have made you a single people, but (His plan is) to test you in what He hath given you: so strive as in a race in all virtues. The goal of you all is to Allah. it is He that will show you the truth of the matters in which ye dispute. [5/48]"

"And this (He commands): Judge thou between them by what Allah hath revealed, and follow not their vain desires, but beware of them lest they beguile thee from any of that (teaching) which Allah hath sent down to thee. And if they turn away, be assured that for some of their crime it is Allah's purpose to punish them. And truly most men are rebellious. 5/49"

Muhammad (p.b.u.h), himself was ordered to hold fast to the revelation


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So hold thou fast to the Revelation sent down to thee; verily thou art on a Straight Way.

Muhammad (p.b.u.h) was ordered to follow only the revelation


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And follow what is revealed to you and be patient till Allah should give judgment, and He is the best of the judges.

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And follow what is revealed to you from your Lord; surely Allah is Aware of what you do;

Muhammad (p.b.u.h) followed only what was revealed to him

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Say: "I tell you not that with me are the treasures of Allah, nor do I know what is hidden, nor do I tell you I am an angel. I but follow what is revealed to me." Say: "can the blind be held equal to the seeing?" Will ye then consider not?

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If thou bring them not a revelation, they say: "Why hast thou not got it together?" Say: "I but follow what is revealed to me from my Lord: this is (nothing but) lights from your Lord, and Guidance, and mercy, for any who have faith."

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But when Our Clear Signs are rehearsed unto them, those who rest not their hope on their meeting with Us, Say: "Bring us a reading other than this, or change this," Say: "It is not for me, of my own accord, to change it: I follow naught but what is revealed unto me: if I were to disobey my Lord, I should myself fear the penalty of a Great Day (to come)."

Quran was the only thing revealed to Muhammad (p.b.u.h)
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Say: What thing is the weightiest in testimony? Say: Allah is witness between you and me; and this Quran has been revealed to me that with it I may warn you and whomsoever it reaches. Do you really bear witness that there are other gods with Allah? Say: I do not bear witness. Say: He is only one Allah, and surely I am clear of that which you set up (with Him).

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We do relate unto thee the most beautiful of stories, in that We reveal to thee this Qur'an: before this, thou too was among those who knew it not.


Since Muhammad (p.b.u.h) followed only what was revealed to him and Quran was the only thing revealed to him, therefore, any Hadith recored in the hadith books that is against Quran, cannot be the saying of Muhammad (p.b.u.h)
Muhammad (p.b.u.h) cannot give any command on his own, because “Command is for none but Allah”.


"If not Him, ye worship nothing but names which ye have named,- ye and your fathers,- for which Allah hath sent down no authority:the command is for none but Allah . He hath commanded that ye worship none but Him: that is the right religion, but most men understand not... 12/44



This information was taken from the link:
http://quranicteachings.co.uk/criterion.htm