(Nayl-ul-Autaar, Qadi Shawkani chapter Salaah Al Taravee).
(Jaami’ Al Uloom Al Hukkam page 252 by Hafidhh ibn Rajjab).
Hafidhh Asqalani writes if a new thing is against Islam, it will be bad. If it is not against Islam, it will be hasanah (Good).
(Fathul Bari chap on Taravi by Hafidhh Asqalani).
Hafidhh ibn Taymiyyah writes that bid’ah is always bad, but some scholars say that there are two kinds of bid’ah, that one is good and one is bad. If a new thing has origin in the Qur’an and Sunnah it will be called Bid’ah Logaviyya (verbally) but not Bid’ah in Shari’ah. Only the word bid’ah will be used on the new things. Like, the Qur’an was collected in one book after the Prophet Muhammad [May Allah bless Him and grant Him peace], and the congregational Taravi prayer was started in Sayyidna Umar’s time but these two things have an origin in the Sunnah. Therefore, it will be called bid’ah verbally.
(Iqtidah al Sirat al Mustaqeem chap on Bid’ah by Hafidhh ibn Taymiyya).
From the above, the conclusion is that if a new thing has been started, and it neither goes against the Qur’an or Sunnah, then it can be declared a ‘good’ innovation. However, if a new act is initiated against the Qur’an and Sunnah, that will be called bad bid’ah, or a reprehensible innovation.
The word Bidah literally means innovations. In Shariah, it means to introduce something new in Deen which was never done before and not part of Deen.
There are two types of innovations, a) Regarded as Deen ? this is absolutely Haraam, and b) Not regarded as Deen, e.g. computers, technology, plans, etc. ? this is not Haraam.
From this, the majority Ulama agreed upon this that there is Bidat Hasanah and Bidah Sayyi-a
a) Bidat Hasanah – everything that is beneficial and does not contradict nor go against the Quraan and Sunnah. It is acceptable and falls under Bidah Hasanah, e.g. construction of Madaaris, hospitals, library, compilation of books. In a Hadeeth Shareef, Rasulullah (Sallallaahu Alayhi Wasallam) encourages us towards those works that will benefit us without going against the Qur?aan and Sunnah.
b) Bidah Sayyi-ah is that which goes agains the Quraan and Sunnat. This is absolutely Haraam, e.g. forming another way of worship, etc. (Maqaalat Kawthari pg.111)
and Allah Ta’ala Knows Best