Kathir bin 'Abdullah bin 'Amr bin 'Awf Al-Muzani said: "My father told me narrating from my grandfather, that the Messenger of Allah said: 'Whoever revives a Sunnah of mine, which people then act upon, will have a reward equivalent to that of those who act upon it, without that detracting from their reward in the slightest. And whoever introduces an innovation (Bid'ah) that is acted upon, will have a burden of sins equivalent to that of those who act upon it, withot that detracting from the burden of those who act upon it in the slightest.'"

Kathir bin 'Abdullah narrated from his father, that his grandfather said: "I heard the Messenger of Allah say: 'Whoever revives a Sunnah of mine that dies out after I am gone, he will have a reward equivalent to that of those among the people who act upon it, without that detracting from their reward in the slightest. Whoever introduces an innovation (Bid'ah) with which Allah and his Messenger are not pleased, he will have a (burden of) sin equivalent to that of those among the people who act upon it, without that detracting from their sins in the slightest.'"