‘Bid’ah and the Salaf’s Worship by Imam Abu al-hasanat Abd al-Hai Lucknawi (rahimahullah) Edited, Revised, and Explainatory by Shaikh Abd al-Fattah Abu Ghuddah (rahimahullah)
To exert oneself in worship is not bid’ah nor is it symbolic of deviation
1) Exertion has been established from the Sahaba radiallahu anhum, Tabi’in and Taba Tabi’in without anyone raising an objection, how could this then be considered as a bid’ah, (under the principles laid down in the earlier chapters).
2) Such exertion has also been related from the Rightly Guided Caliphs like Uthman and Umar Radiallahu anhuma. Whatever has been established by the Caliphs, without an objection being raised upon it, is a sunnah. The sunnah is not specified to only that which was established by the Prophet salalahu alayhi wa salam, but rather it is comprehensive of what was instituted by the Rightly Guided Caliphs radiallahu anhum irrespective of the fact that it was established by one or all of them. And whatever they introduced into the Din and were pleased with, shall be accepted (as a part of the Shari’ah), even though they may not have performed it themselves.
This principle has been explained by Ibn al-Hummam in Tahrir al-Usul   and by Allama al-Aini in Binayah  (may Allah have mercy upon them all) the commentary of al-Hidayah, Abd al-Aziz al-Bukhari (rahimahullah)  in al-Kashft  and by many other Fuqaha and Usuliyun. A thoroughevluation of this issue can be found in my book, Tuhfat al-Akhyar. 
Thus, when an action is established as being a Sunnah, then ultimately it can no longer remain a bid’ah, because one is incompatible with the other.
3) These glorious deeds and illustrious feats were the practice of the Mujtahid Imams, the eminent Fuqaha and the Muhaddithin. If these actions were tantamount to bid’ah, then all of the aforementioned are innovators and astray. Such a notion is flawed by the consensus of those who are ranked accoutnable in matters of religion from this Ummah.
4) The most prominent historians and compilers of the biographies of the narrators of ahadith, upon whom the Ummah is unanimous in reliance, their piety and caution of bid’ah is renowened. These distinguished figures have frequently related the exertion of the scholars in a rank and status of appraisal and glorification, while dealing with their biographies. Is this not a proof in itself that they did not consider exertion in worship a bid’ah, because the appraisal of a bid’ah is not befitting the characteristics of eminent Imams.
 Allama Kamal al-Din Muhammad ibn Abd al-Wahid al-Sayuwasi al-Sakandari(rahimahullah), the author of Fath al-Qadir which is the commentary of al-Hidayah, and many other works. He was born in 790A/H and studied fiqh under Siraj (qari al-Hidayah). He excelled his contemporaries in many sciences and was an incontestable Hanafi scholar. He passed away in 861 A/H as is mentioned in Husn al-Muhadarah. (Author)
 Allama Abd al-Aziz ibn Ahmad ibn Muhammad al-Bukhari (rahimahullah). A hanafi in jurisprudence. He authored works such as al-Kashf the commentary of Usul al-Bazdawi, al-Tahqiq the commentary of al-Muntakhab al-Husami and many others. He studied fiqh under his uncle Fakhar al-Din Muhammad ibn Muhammad Ilyas al-Mayumraghi(rahimahullah) who was the student of Shams al-A’imma Kardari (rahimahullah) as is stated in A’lam al-Akhyar. The shaikh passed away in 730 A/H as mentioned in Kashf al-Zanun. (Author)