there are some who do not admit the infallibility of the   prophet, and they depend on some evidence as for example the chapter of (abasa (he frowned) :chapter no.80 ) and also when the prophet (pbuh) flattered his wives and the holy verse descended from allah to order him to stop that.

- the reply on this suspicion

  the infallibility of the prophet (pbuh) and the infallibility of all messengers (pbut) should be understood in the limits of the position of the messenger and the purpose of the message, that the messenger is a human being who is inspired by allah;  which means that in spite of his human qualities, he has a special contact with the heaven by inspiration. so this task needs some characteristics which are found by the almighty allah in all messengers chosen for this task to balance between their human characteristics and their position and special task which they are demanded for.

 the messenger is commissioned to tell ,call for, and fight for applying and setting the message up. and people were ordered to obey the messenger as apart of obeying allah (glory be to him):

 "obey allah and obey the messenger" (an nissa’: 59)

"he who obeys the messenger (muhammad), has indeed obeyed allah" (an nissa’:80)

" say (o muhammad to mankind): "if you (really) love allah then follow me (i.e. accept islamic monotheism, follow the qur'an and the sunnah), allah will love you "( aal imraan:31)

"say (o muhammad): "obey allah and the messenger (muhammad)” (aal imraan:32)

 so the infallibility of the messengers in what they tell about ِallah is necessary for believing and trusting the divine call which the messengers are chosen to fulfill.

the nature of mind besides won’t believe in this message unless the sender of the message chooses the trustful messenger in order to make his message believable and truthful. so allah chooses carefully his messengers whom he qualifies by infallibility to add more truth and trust upon the divine call. and this infallibility at the same time is the evidence that this call is right.

in order  to express the general point of view of the islamic nation in the necessity of the  infallibility of all messengers in what they tell about the almighty allah ,imam mohammed abdo says:-

“....and these necessary things that must found in messengers are: their high innate, wise minds, truthfulness, integrity in telling what they are commanded, infallibility against what disgraces their reputation, good looking bodies and that their souls are so linked with the divine greatness that their inner feelings can not control them .

 out of the wisdom of the almighty creator- who created man upon the base of education and guidance-he left one important quality -out of his generosity - for the people whom he chose from his creatures to carry his message. so he favors his messengers by high sense innate and raises their souls high to reach the perfection in order to be ready for receiving and keeping the secrets of the divine lights of knowledge.

by this knowledge allah permits his messengers to know some of the future and what will happen to people in the future. the messengers live among people in a high rank; they are in life as they are not from its people, they are not like the people in their contacting and telling about the heaven, but in the same time they have their human sides e.g. they eat, sleep, drink, forget-except in addressing about allah and his teachings-, get sick, get harmed, get oppressed and may get killed.

infallibility, like a miracle, is one of the necessities of the message’s trustfulness and the wisdom of the one who sent all messengers (peace be upon them).the messenger is like any ordinary man, physically his body is like all other people, and as a diligent person he is making consultations, making up his mind, thinking and choosing between many choices in matters that no divine inspiration is given to him. here he has to act according to his human side; so he may be right and may be wrong.

 but he is infallible in the topics and cases which are inspired to him from the almighty allah, because if he may forget or be wronged in such cases, people will doubt his message. so infallibility is an original characteristic and a necessary condition in all messengers (peace be upon them).

"nor does he speak of (his own) desire. it is only an inspiration that is inspired". (an-najm 3,4) 

the messenger’s utterances are not the human ones; it means that his orders are the orders of allah, so obeying him is obeying allah and without infallibility messengers can not get such high rank.

the exertions of the prophet (pbuh) in the cases that he doesn’t get the solution inspired were a result of his human abilities and making up his mind so he may be right and may be wrong as it happen to all people. so we see how his companions -may allah be pleased with them - in many cases ask muhammad (pbuh) -before giving their points of view- whether his point of view or his exertion .. etc is inspired to him or not . if he says that it is a divine inspiration they obey him with no question, because here obeying him is obeying allah who asks him to tell his orders.

for the orders of allah, messengers are infallible in telling them, that they are just tellers where there is no place for committing mistakes. and the companions obeyed the orders of the messenger blindly even if they can not understand the near benefits from these orders, because they know that the knowledge of allah- the source of inspiration- is unlimited but their knowledge is limited; they may not understand the wise reasons behind these laws but the almighty allah only knows.

but when the messenger tells his companions that his exertion expresses his own point of view and it is not inspired to him, at once they give their points of view. they think and correct his decisions if he is mistaken because here he depends only on his human qualities which may be right or wrong.

there are a lot of examples in the books of sonna and in the biography of muhammad which prove that he changed his opinion when he found that there is on better than his’;e.g. when they wanted to choose the place of their camp in the battlefield of badr:

(it happened that there was a well in the battlefield it was called badr and the messenger (pbuh) chose to camp behind the well. then one of the companions called elhabab ibn almunther came and asked the messenger if their position was chosen by allah or it was just his  opinion, the messenger replied that this was his opinion. alhabab said that it was a bad position and they should put the well in their back to drink from it and prevent quraish from drinking from it; and so they did. many other examples; as their point of view in the captives of the battle of badr and their point of view in making peace with some of those who were from the allies against the muslims in the battle of the trench.........etc.

 allah wants for muhammad to be the model and the example for the whole nation to follow:

"indeed in the messenger of allah (muhammad ) you have a good example to follow for him who hopes in (the meeting with) allah and the last day and remembers allah much".( al-ahzâb: 21 )

and because allah does not want for the people to take  a wrong prophetic exertion  as a model, he sent the inspiration to correct and even blame the prophet for his wrong exertions  and choices e.g.

"(the prophet) frowned and turned away*because there came to him the blind man (i.e. ‘abdullâh bin umm-maktûm, who came to the prophet while he was preaching to one or some of the quraish chiefs)*and how can you know that he might become pure (from sins)?*or he might receive admonition, and the admonition might profit him?* as for him who thinks himself self-sufficient, to him you attend; what does it matter to you if he will not become pure (from disbelief: you are only a messenger, your duty is to convey the message of allâh).but as to him who came to you running,and is afraid (of allâh and his punishment).of him you are neglectful and divert your attention to another,"

(abasa:1-10 )

"o prophet! why do you ban (for yourself) that which allah has made lawful to you, seeking to please your wives? and allah is oft-forgiving, most merciful.  allah has already ordained for you (o men), the dissolution of your oaths. and allah is your maula lord, or master, or protector, etc.) and he is the all-knower, the all-wise.  and (remember) when the prophet disclosed a matter in confidence to one of his wives (hafsah),so when she told it (to another i.e. 'aishah), and allah made it known to him, he informed part thereof and left a part. then when he told her (hafsah) thereof, she said: "who told you this?" he said: "the all-knower, the all-aware (allah) has told me". 

( at-tahrîm :1-3 )

 "it is not for a prophet that he should have prisoners of war (and free them with ransom) until he had 
made a great slaughter (among his enemies) in the land. you desire the good of this world (i.e. the money of ransom for freeing the captives), but allah desires (for you) the hereafter. and allah is all-mighty, all-wise.  were it not a previous ordainment from allah, a severe torment would have touched you for what you took." 

 (al-anfâl :67-68 )

 the infallibility of the messenger (may peace and prayers of allah be upon him) is a necessary condition in order to prove the truth of the message and to gain confidence on the divine call. and without this infallibility there will not be any difference between the messenger and any other reformer or wise man. and so there will not be any difference between the invincible and infallible inspiration and the human philosophies and achievements which may be right or wrong. without infallibility the message become as the human utterances but with the infallibility the message becomes the utterances of allah -glory be to him-who is giving his words to the infallible person (all prophets & messengers).so the infallibility of the teller proves the infallibility of the message, and it is also the condition that proves the wisdom of the one who chose the messenger, sent and inspired him this message.