People often misunderstand Islam. Sometimes a belief and practice of Islam was not regarded as Islamic and sometimes a belief and practice of Islam is not considered that it is Islam. How could this happen? That's because many people do not understand about Islam. This does not only happen to ordinary people but also the intellectual. And felt really need to be understood by everyone will be understanding of Islam so that people do not get me wrong and it should be taken from the original source ie the Qur'an, not from the opinions of other people or who. And Allah is not impossible to explain in express or implied in the Qur'an in this case. And I have found an explanation.
The word Islam is derived from the Arabic al-Islam. Al-Islam said in the Qur'an and also the meaning contained therein, including in the letter of Ali Imron (3) verse 19 and surah Al-anymore (5) of ayat 3. What can we understand from the second verse?.
Al-Qur'an letter Ali Imron (3) of ayat 19, pronunciation, "innad-dina 'indallohil-Islam ..." meaning, "the real ad-din (way of life) on the side of Allah (is) al-Islam ...." This verse clearly states that al-Islam is the name of an ad-din (way of life) by the side of Allah ('indalloh). She is from Allah, so named also dinulloh (QS 110 ayat 2), an ad-din set by Allah to mankind. He is not the idea or the fruits of human thought. Up to humans only through the revelation of Allah to prophets and rosul. And al-Islam in its final (perfect) fell to the Prophet and the last is rosul, Muhammad, with the intercession of the Holy Qur'an and its explanation.
Then Al-Quran surah Al-anymore (5) of ayat 3, pronunciation, "... al-wa yauma akmaltu Lakkum dinakum atmamtu 'alaikum wa ni'mati rodhitu-islama lakumul dina ...". The word "al-yauma" means "today", ie the day the decline of this ayat, namely on Friday in the desert Arofah after the time when Muhammad ashr perform the Farewell Hajj. Then the phrase "akmaltu Lakkum dinakum" meaning, "have I perfected for you your ad-din." You said the phrase "ad-din you" referred to was the Prophet Muhammad and his companions, so "ad-din you" mean Dinu Muhammadin PBUH and his companions in the form of belief forms ('aqidah) and deeds (' amal), which exist in Muhammad's (individually) and the Companions (the community) which is the implementation, interpretation, explanation of the Qur'an on direct instructions from Allah Almighty which of his al-Islam is derived (Sura 3 verse 19 ), so to say "have I perfected for you your ad-din." Then the phrase "wa-islama rodhitu lakumul dina", which means, "and I have blessing of al-Islam as ad-din for you." In this sentence Dinu Muhammadin mention Allah's Messenger and his companions as al-islam. And therefore in this ayat used the word "ad-din", the word in the singular and the plural is "al-adyan", then this means Dinu Muhammadin and the Companions of Allah is one, together. And because Muhammad is the party that received the revelation (the Qur'an) and arguments (Sura 75 verses 16-19) and he saw with perfect devotion he received the revelation (Sura 33 verse 2) and the companions are the most excited person He followed the Prophet in (Sura 3 verse 31) and they are the main reference in understanding al-Islam for those who live after them (Sura 9 verse 100), then al-Islam is certainly no other or millatu Dinu Muhammadin Muhammad PBUH or sunnatu Muhammadin path of Allah or Muhammad (peace be upon him but not he who raise) or others have called with As-Sunnah. So al-Islam is as-Sunna and al-Sunna is al-Islam. So a belief and deeds that do not exist in the as-Sunna can not be called al-Islam. And more will clarify this is the word of Muhammad, pronunciation, "man 'amila' practice laisa 'alaihi amruna fahuwa roddun" meaning, "Those who do good with a practice that is not available to us (ie he saw and his Companions ) then the (practice it) rejected "(Muslim," 'A'ishah). Why rejected? because it means instead of al-Islam and Allah only accepts only of al-Islam (Sura 3 verse 85).
Muhammad and his companions were a group of people who most understand al-Islam and therefore they are praised by Allah as "khoiru umma" (the best people) (Sura 3 verse 110). The name was given not because of technological progress or anything, but more is because they believe in and practice of al-Islam with the best.
We who live in the age now know al-Islam only from the Qur'an and Sunnah, and recorded in the hadiths that Shohih. So that we can easily find out whether the belief or action that includes al-Islam or not if we know a lot about the Qur'an and hadiths that Shohih. If there is essentially within the Qur'an and Sunnah which is shown by the hadith which Shohih is certain that al-islam. If not there is basically how it is called al-Islam?