Is this narration authentic?
لترك ذرة مما نهى الله عنه أفضل من عبادة الثقلين
This narration is cited in several Fiqh/Usulul Fiqh books without a chain. I have not come across the complete chain and therefore cannot comment on the authenticity.
(Refer: Kashful Asrar ‘An Usuli Fakhril Islam, vol. 1 pg. 91)
Although the words in question should not be quoted as a Hadith until the chain can be located, abstinence from sin has been mentioned in other Hadiths to be a great act of worship. See here.
And Allah Ta’ala Knows best.
Answered by: Moulana Suhail Motala
Approved by: Moulana Muhammad Abasoomar