Veneration of Muhammad
Muslims have many ways to express veneration for Muhammad, as an acknowledgement of him being the final prophet of Islam, with one special exception: Muslims do not worship Muhammad, out of belief in the oneness of God as stated in the Shahada.
The sinlessness of Muhammad
All Muslims believe that Muhammad was sinless in the sense of transmitting the revelation.
Mainstream traditional Sunni believes that Muhammad was infallible and sinless. They believe that, as a Prophet of Islam, he was protected by Allah. According to Sunni scholars, if the messenger is not error-prone then the message will connotatively lack credentials of authenticity.
- Qadi `Iyad in al-Shifa' said that the Jumhur Majority of the jurists from the schools of Hanbali, Maliki, Shafi`i, and Abu Hanifa, agree that the prophets are protected from all sins because one is required to follow them in the minutest matters.
Allah Most High preserving the Prophets from falling into that which has been prohibited," as explained by the commentators of the Jawhara. [Tattan/Kaylani, `Awn al-Murid `ala Jawharat al-Tawhid, 2.727; also: Bajuri, Tuhfat al-Murid].
They put forward following verses ,
Allah Most High has commanded us in the Qur'an to follow the Prophets in numerous verses that are decisive (qat`i) in their indication--such as, "These are the ones whom Allah has guided, so follow their guidance.Quran, Surah Al-Anam 90.
God made a covenant with the believers that if they obey Him, assist His cause and strive to exalt His Word, by proclaiming His religion, He will help them and make their feet firm in the religion, protecting them against all kinds of deviation Muhammad, 47.7.
O Messenger! Convey what has been sent to you from your Lord. If you did not, you would not have fulfilled His mission. And God will defend you from people. Certainly, God guides not the unbelieving people. Al-Maida,5.67
The doctrine of sinlessness in Shia'ism is called Ismah (Arabic: عِصْمَة, Persian: ِعصمت) literally means 'protection' and is generally translated as "sinlessness". Protection is believed to be of three types of "Protection from mistake in receiving the revelation from Allah", "Protection from mistake in conveying the revelation of Allah" and "Protection from sins." It is believed that all the prophets in Islam, Fatima, and the twelve descendants of Muhammad through Fatima are sinless. 
The Shi'a teaches that Muhammad, Fatima together with the twelve descendants of Muhammad through Fatima are purified by God (See the Event of the Cloak). They are commonly called fourteen infallibles. Though the fourteen infallibles are human being and may be tempted by Satan towards sin, it is believed that they will be helped by God to overcome Satan’s temptations. The following verse of Qur’an is sometimes cited to prove this position.
- (Satan) said: "O my Lord! because Thou hast put me in the wrong, I will make (wrong) fair-seeming to them on the earth, and I will put them all in the wrong,- Except Thy servants among them, sincere and purified (by Thy Grace)." (15:39-40)
What was the fate of Muhammad's soul after his death?
Most Muslims believe that Muhammad performed miracles, such as splitting the moon. They also believe the Quran is the living miracle given to Muhammad by Allah.
In speaking and writing
When speaking or writing, Muhammad's name is often followed by the phrase "peace be upon him," in English often abbreviated to PBUH or simply "(p)".
Muhammad is often referenced with titles of praise:
- al-Mustafa, "the chosen one"
- ar-Rasûl, "the Messenger"
- an-Nabi, "the Prophet"
- al-Khatim, "the last [prophet]"
- al-Ummi, "the unlettered one"
- al-Amîn, "the trustworthy"
- as-Sadîq, "the truthful"
- al-Mutawkkil, "the one who puts his trust [in God]"
- al-Kuthâm, "the generous one"
- al-Fatih, "the opener"
- al-Mahi, "the eraser [of disbelief]" 
- al-Hashir, "the gatherer (the first to be resurrected)" 
- al-Aqib, "the last [prophet]" 
- ad-Dahuk, "the one who smiles, the cheerful one"
- Ahmad, "the chosen one" 
Praise in poetry and music
Islamic poetry is rich in the praise of Muhammad. Rarely is there any Muslim poet who is without any piece written on him. In fact there is a special class of poetry, known as Nasheed (Arabic) or Naat (Urdu), devoted to such praise. This is inspired by the Islamic traditions (ahadith) that each act of veneration would result in 10 times the blessing of God on the praiser. (see Praise of Muhammad in poetry).
The birthday of Muhammad
Many Shias, Sufis and some Sunnis celebrate Muhammad's birthday with elaborate festivities. Cities and homes are illuminated with colorful lights and candles, parades and processions are carried out, and conferences on the life of Muhammad are held. Many Sunni groups feel that such celebrations are idolatry or shirk or innovations and forbid them.
Punishment of criticism
Criticism of Muhammad is often equated with blasphemy, which is punishable by death in some Islamic states.
In 2005 a Danish newspaper, the Jyllands-Posten, printed some controversial cartoons, most of which were insulting toward Muhammad and Islam. Some countries -- Saudi Arabia, Turkey, and Iraq among them -- protested vigorously to the Danish government for not taking action against the newspaper, but the Danish government responded that it does not control the media.
While most of Islam was predominantly aniconistic during most of its history, there are rich traditions of visual representation of Muhammad, mainly in the form of paintings and illustrations in religious or hagiographical texts. Religious figures rarely have their face shown. Such figures are often shown with their head veiled in sheets embroidered with Koranic text. Sunni Islam discourages representations of any religious figure, whereas Shi'as do not have such prohibitions, as there are many images of their imams, including Ali.
- ↑ 1.0 1.1 Understanding the Sinlessness of Prophets and their Reprimand in the Qur'an
- ↑ The Global Islamic Community Forums - Can Prophets (‘alayhimus salātu was salām) commit Mistakes?
- ↑ How Are The Prophets Protected From Error And Sin?
- ↑ What do we believe about the Prophet's knowledge of the Unseen?
- ↑ Infallibility of Prophets
- ↑ Are Prophets of Allah not Sinless?, by Ali A. Khalfan, May 07, 2005, retrieved March 27, 2006
- ↑ ShaikhSiddiqui Barelvi
- ↑ Major sects in Islam - YaNabi.com
- ↑ 9.0 9.1 9.2 9.3 Sahih Bukhari 
- ↑ Man ‘declared infidel’ killed by mob -DAWN - Top Stories; 21 April 2005