I found a quote attributed to Imam Ali (as): 'Ma min āyatin fī Kitābi-llāh illā amlāhā Rasūlullāh wa khattahā bi-yadī.' Could you provide information on the source of this statement and its authenticity?
This is an authentic quote from Ameerul Mo'mineen Ali (AS) narrated from him in both Sunni and Shia books e.g. al-Kaafi 1:64
, Biharul Anwaar, V.89, Page 99,
The well known Sunni book : Shawahid al-Tanzeel by Al-Hasakaani 1:43
The statement confirms the full knowledge of Ameerul Mo'mineen Ali (AS) about every verse in Quran.
Wassalam.