Correcting Imam in Salaah

Q: At my local mosque during Esha prayer I gave luqmah (correction) to the imam as I thought he read something wrong. After the salaat an alim (scholar – not the imam) approached me and explained to me I should not give luqmah if the imam has read 3 or more ayaat (verses) in respect of the imam unless the imam made such a mistake which ulama (scholars) know better which makes it necessary to give luqmah. I don’t know if this was the right thing said to me. Please explain.  

A: What he said is correct. After 3 Aayaat, luqmah will be given if it is a serious error, otherwise not.

Moulana Yusuf Laher