First of all, we would like to stress that Sunnah refers to what has been traced back from the Prophet whether sayings, actions or tacit approvals. Fiqh on the other hand, refers to the sayings of the jurists as deduced from the original sources of Islam.

It should be noted that: not all new things are innovations that are prohibited in Islam. In fact, what Muslims need these days is to understand Islam correctly, without negligence or extremism. Not all novel and new things are bad in Islam; rather Islam does ask Muslims to be innovative and creative in the social, economical, cultural, and political fields so as to serve their societies and humanity in general. Innovation in religion is what Muslims must be cautious of lest they invent what is un-Islamic.

In this regard, Dr. Muzammil H. Siddiqi, President of the Fiqh Council of North America, states:

The word bid`ah literally means “something new; an innovation.” But as a term (istilah), it is explained in different ways.

Some scholars consider everything new as bid`ah. However, if that new thing has some basis (asl) in the Shari`ah to make it acceptable, then they call it bid`ah hasanah (good innovation). But if it has no basis in the Shari`ah, then they call it bid`ah sayyi’ah (bad innovation).

However, there are some other scholars who do not call any action, however new it may be, as bid`ah as long it has a basis in the Shari`ah. They would call bid`ah only those actions that have no evidence or foundation in the Shari`ah to make them acceptable.

Moreover, we’d like to state that Muslim scholars have cited two different definitions of Bid`ah (innovation). The first one is linguistic, whereas the second is technical.
Those who try to understand the concept of Bid`ah in its linguistic sense maintain that the root of the word includes that which is new and unprecedented. Hence, they define Bid`ah as everything that has been introduced following the death of the Prophet (peace and blessings be upon him) and the golden eras of his Companions (may Allah be pleased with them all).
the aforementioned linguistic definition encompasses what is good and what is bad, acts of worship (`Ibadat) and others that are otherwise. Those who follow this definition argue that the word Bid`ah as well as the acts related to it are praised in certain religious contexts while condemned in others. This may explain why some scholars have dubbed certain innovative acts as being religiously recommended while classifying others as being rel
igiously condemned.
Imam Shafi`i stated that innovative acts are of two kinds: the first one includes those things that do not go in harmony with the Qur’an, Sunnah, traceable tradition (Athar) and the consensus (Ijma`) of Muslims. The second kind includes those innovations that bring about that which is good and this kind is not condemned.
the previous classification of Bid`ah is also maintained by Imam An-Nawawi.
however, Imam Al-`Izz ibn `Abdus-Salam classified Bid`ah into five categories:
1-Obligatory innovation, such as combining and classifying Arabic sciences and teaching them.
2-Religiously recommended innovation, such as building schools.
3-Religiously forbidden innovation, such as reciting the Qur’an in a way that changes the meaning of its words from their contexts.
4-Religiously condemned innovation, such as decorating mosques.
5-Religiously permitted innovation, such as serving different dishes on one dining table.
On the other hand, those who adopt the technical definition of Bid’ah state that innovation includes things that apparently resemble Shari`ah, but genuinely they don’t. On the basis of this definition, all innovations are strongly condemned, and hence they can not include the five categories mentioned by Imam Al-`Izz ibn `Abdus-Salaam above. This may explain the Prophetic saying, “Every innovative act is an aberration.”
also, Imam Malik stated that he who innovates something in Islam while deeming it to be a good innovation has alleged that Muhammad (peace and blessings be upon him) was unfaithful in disseminating his message as Allah Almighty says: “This day are those who disbelieve in despair of (ever harming) your religion; so fear them not, fear Me! This day have I perfected your religion for you and completed My favor unto you, and have chosen for you Al-Islam as religion. Whosoever is forced by hunger, not by will, to sin: (for him) Lo! Allah is Forgiving, Merciful.” (Al-Ma’idah: 3)
hence, the innovations that are unlawful in Islam include the following:
1-Being innovated, in the sense that the innovation does not take place during the early Islamic period.
2-The innovation is considered unlawful when it contradicts one of the primary sources of Islam, such as the Qur’an and the Sunnah.
as a result, things that are new and unprecedented, but go in line with the spirit of Islam, and do not contradict its basics are not considered innovations. It is recorded that some of the Prophet’s Companions (may Allah be pleased with them all) would say the Talbiyah (during Hajj) in a formula different from that said by the Prophet (peace and blessings be upon him). For example, Anas (may Allah be pleased with him) would say, “Labbayka Haqqan Haqqa Labbayka Ta`abbudan Wa sedqa.” ‘Truly I am at your service O Allah; I am at your service in true worship of You.’
also, `Umar (may Allah be pleased with him) is reported to have gathered people to perform Tarawih (Ramadan night prayer) in congregation. It is noteworthy here that the same act did not exist during the lifetime of the Prophet (peace and blessings be upon him).

Based on what is mentioned above, we do stress that bid`ah is of a wider concept as stated above, and hence a Muslim should try his best to seek true knowledge from the original sources while asking about whatever ambiguous matter that may occur to him.