I am having suspicions and doubts.I was reading around on the internet and read somewhere that hadiths were collected after the prophet Muhammad (p.b.u.h) time and therefore many of them are not authentic.I also read that muslims have so many sects.Now every time I read fazail e amal or a hadith , I start getting worried about its authenticity.I worry if im doing a biddah , or if by following or reading a book by particular imam , im being a part of a sect.I only want to be a muslim .I know sunnah is necessary , it explains how to say prayers and other necessary things.But doubt arises , like when I am doing wuzu by following sunnah way , I start thinking should wuzu be done as mentioned in quran(farz) way or sunnah way?.im confused ..and worried .Also I get doubts when saying astaghfar that should I do it a 100 times or say it without counting.
In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
Your doubts stem from the misconception that the Ahadith were not collected or written during the time of Rasulullah صلى الله علىه وسلم
The reality is Ahadith were written during the time of Rasulullah صلى الله علىه وسلم. : There are numerous Sahabah who used to write the Ahadith of Rasulullah صلى الله علىه وسلم .
Some of them are:
This was the Hadith compilation of Hazrat Abdullah ibn Amr ibn al-Aas رضي الله عنه.
Hazrat Abu Hurairah رضي الله عنه narrates that:
عن أبي هريرة قال: “ما مِنْ أصحابِ النبيِّ – صلى الله عليه وسلم – أحدٌ أكثرَ حديثاً عنه منِّي؛ إِلا ما كانَ من عبدِ الله بنِ عمْروٍ؛ فإِنه كانَ يكتبُ، ولا أَكتبُ”.
None of the Sahabah gathered more Ahadith than I besides Hazrat Abdullah ibn Amr ibn al-Aas .That is because he used to write and I would not write.
Hazrat Abu Hurairah رضي الله عنه narrations are approximately 5374.
2.Sahifaat Hazrat Ali رضي الله عنه
In this compilation, the laws of Diyyat (blood money), Fidyah (compensation) and Qisaas (capital punishment) were written by Hazrat Ali رضي الله عنه.
3. Kitabul Sadaqah
This is a compilation of Ahadith pertaining to Sadaqah (voluntary charity) and Zakaat (compulsory charity due to poor) dictated by Rasulullah صلى الله علىه وسلم which was passed over to Hazrat Abubakar رضي الله عنه.
Many Ahadith are traced up to these written compilations of the Sahabah. Furthermore, it is a well-known fact that every Sahabi is honest.
Many Sahabah narrated Ahadith through their memories which were supported and collaborated through the narrations of other Sahabah.
This science of authenticating Ahadith is called Al-itbar in which every narrator in the chain of narrators is heavily scrutinised before accepting his narration.The history of each narrator is documented in detail in the books of Asmaul Rijaal.
Furthermore it can be safely claimed that every authentic Hadith is traced to a written compilation of Ahadith at the time of Rasulullah صلى الله علىه وسلم and the claim of authenticity of every Hadith can be substantiated with overwhelming proof that satisfies ones conscious.
Fazail-e-Aamal is compiled by Hazrat Sheikh Zakariyyah رحمه الله who was an authority on Hadith. His innumerable works on Hadith are appreciated by great Ulama of our times.
There is no reason for you to doubt the Ahadith of Fazail-e-Aamal or any authentic Hadith book. The doubts are waswas of Shaytan that will deprive you of the barakah and blessings of Ahadith. Simply recite لا حول ولا قوة الا بالله and benefit from the compilations of Ahadith by reliable Ulama. [i]
And Allah Ta’āla Knows Best
Student Darul Iftaa
Checked and Approved by,
Mufti Ebrahim Desai.
 Al Tahzib wal Tahzib Volume 8 Page 53 Dar al-Kitab al-Islamiy
Sahih al-Bukhari Volume 1 Page 59 Qadimi Kutub Khana
 Sahih al-Bukhari Volume 1 Page 21 Qadimi Kutub Khana
 Sunan al-Tirmizi Volume 1 Page 79 Meer Muhammad Karachi.
[i] Differences of the Ummah-Moulana Yusuf Ludhyanwi رحمه الله
The Maslak of the Ulama of Deoband-Hazrat Qari Tayyib رحمه الله
Authority of Sunnah-Mufti Taqi Usmani Saheb-حفضه الله
Kashful Baari-Moulana Saleemullah Khan Saheb حفضه الله
Introduction to Hadith-Mufti Ebrahim Desai Saheb حفضه الله