One day after the morning Salat, the Messenger of Allah (ﷺ) exhorted us to the extent that the eyes wept and the hearts shuddered with fear. A man said: 'Indeed this is a farewell exhortation. [So what] do you order us O Messenger of Allah?' He said: 'I order you to have Taqwa of Allah, and to listen and obey, even in the case of a Ethiopian slave. Indeed, whomever among you lives, he will see much difference. Beware of the newly invented matters, for indeed they are astray. Whoever among you sees that, then he must stick to my Sunnah and the Sunnah of the rightly guided Khulafa', click to it with the molars.'

narrated from his father, from his grandfather that the Prophet (ﷺ) said to Bilal bin Al-Harith: Know. He said: I am ready to know O Messenger of Allah! He (ﷺ) said: That indeed whoever revives a Sunnah from my Sunnah which has died after me, then for him is a reward similar to whoever acts upon it without diminishing anything from their rewards. And whoever introduces an erroneous innovation which Allah is not pleased with, nor His Messenger, then he shall receive sins similar to whoever acts upon it, without that diminishing anything from the sins of the people.'