The Messenger of Allah ﷺ said, "Whoever calls others to guidance will receive a reward equal to the rewards of those who follow him, without diminishing their rewards in the least. And whoever calls others to misguidance will bear sin equal to the sins of those who follow him, without diminishing their sins in the least."
أن رسول الله ﷺ قال: من دعا إلى هدى كان له من الأجر مثل أجور من تبعه لا ينقص ذلك من أجورهم شيئا، ومن دعا إلى ضلالة كان عليه من الإثم مثل آثام من تبعه، لا ينقص ذلك من آثامهم شيئا.
Muslim narrated it in the Book of Knowledge (2674) through multiple routes from Ismail bin Jafar, from Ala, from his father, from Abu Hurairah, and he narrated it.With the same meaning is what was narrated from Abu Juhayfa, who said, the Messenger of Allah ﷺ said, "Whoever introduces a good sunnah which is then acted upon after him will have his own reward and the like of the rewards of those who act upon it, without anything being diminished from their rewards, and whoever introduces a bad sunnah which is then acted upon after him will bear his own burden and the like of the burdens of those who act upon it, without anything being diminished from their burdens." Ibn Majah narrated it (207) from Muhammad bin Yahya, who said, Abu Naeem narrated to us, Ismail Abu Israil narrated to us, from Hakam (that is, Ibn Utayba), from Abu Juhayfa, and he narrated it. In its chain is Ismail Abu Israil, who is Ibn Khalifa Malai, weak in memory.With the same meaning is what was narrated from Anas bin Malik, from the Messenger of Allah ﷺ, that he said, "Whatever caller calls to misguidance and is followed will have the like of the burdens of those who follow him, without anything being diminished from their burdens, and whatever caller calls to guidance and is followed will have the like of the rewards of those who follow him, without anything being diminished from their rewards." Ibn Majah narrated it (205) from Isa bin Hammad Misri, who said, Layth bin Saad informed us, from Yazid bin Abu Habib, from Saad bin Sinan, from Anas, and he narrated it. Saad bin Sinan is daif, and Busiri faulted the hadith on this basis in Misbah Zujaja.Nor is it correct, what was narrated from him as a raised hadith, "There is no caller to anything but that he will be held standing on the Day of Resurrection, bound to it, unable to part from it, even if a man merely called another man," then he recited the words of Allah , "Stop them, for they are to be questioned. What is wrong with you that you do not help one another?" [Saffat 37:24–25]. Tirmidhi narrated it (3228) through the route of Mutamir bin Sulayman, who said, Layth bin Abu Salim narrated to us, from Bishr, from Anas bin Malik, and he narrated it. Layth bin Abu Salim's memory became confused, and he was inconsistent in the chain of this hadith. Ibn Majah narrated it (208) through the route of Abu Muawiya, from Layth, from Bashir bin Nuhayk, from Abu Hurairah, from the Prophet ﷺ, with similar wording, without mentioning the verse. This is why Tirmidhi said following the hadith of Anas, "This is an unusual hadith," meaning daif.Likewise, it is not correct, what was narrated from him as a raised hadith, "There is no man who revives a truth with his tongue, which is then acted upon after him, except that his reward continues to flow to him until the Day of Resurrection, then Allah will settle his account in full on the Day of Resurrection." Ahmad narrated it (13803) from Ali bin Ishaq, who said, Abdullah (that is, Ibn Mubarak) narrated to us, Ubaydullah bin Mawhab informed us, from Malik bin Muhammad bin Haritha Ansari, that Anas bin Malik said, and he narrated it. Regarding Malik bin Muhammad bin Haritha Ansari, Husayni said, "There is doubt about him." Ibn Hajar said in Tajil (998), "He is Malik bin Abu Rijal." I say, if he is indeed Malik bin Abu Rijal, then his narration from Anas is disconnected, as stated in Jarh wa Tadil (8/216).As for what was narrated from Kathir bin Abdullah, from his father, from his grandfather, who said, I heard the Messenger of Allah ﷺ say, "Whoever revives a sunnah of mine that has died out after me will have a reward equal to the reward of those among the people who act upon it, without anything being diminished from the people's rewards, and whoever introduces an innovation with which Allah and His Messenger are not pleased will bear a sin equal to the sin of those among the people who act upon it, without anything being diminished from the people's sins," its chain is daif. Tirmidhi narrated it (2177) and Ibn Majah (209, 210), both through routes from Kathir bin Abdullah bin Amr bin Awf Muzani, from his father, from his grandfather, and he narrated it. Tirmidhi said, "This is a hasan hadith."I say, in its chain is Kathir bin Abdullah bin Amr bin Awf Muzani, who is daif by the consensus of the scholars. This is why Tirmidhi was criticized for grading this hadith hasan. As for his father, Abdullah bin Amr bin Awf, I have not found anyone who deemed him reliable, except that Ibn Hibban mentioned him among his trustworthy narrators. This is why Ibn Hajar said, "acceptable," meaning when corroborated, and I have not found any corroboration for him.Likewise, it is not correct, what was narrated from Anas bin Malik, who said, the Messenger of Allah ﷺ said to me, "My son, if you are able to wake and to sleep at night with no malice in your heart toward anyone, then do so." Then he said to me, "My son, that is part of my sunnah, and whoever revives my sunnah has loved me, and whoever loves me will be with me in Paradise." Tirmidhi narrated it (2678) from Muslim bin Hatim Ansari, who said, Muhammad bin Abdullah Ansari narrated to us, from his father, from Ali bin Zayd, from Saeed bin Musayab, from Anas bin Malik, and he narrated it. Tirmidhi said, "This is a hasan hadith, unusual from this route."I say, Ali bin Zayd, who is Ibn Jadan, is daif. The majority of scholars deemed him daif, even though Tirmidhi held a favorable opinion of him.Tirmidhi said following the aforementioned hadith, "I discussed it with Muhammad bin Ismail, and he did not recognize it, and he did not know of this hadith, nor any other, from Saeed bin Musayab from Anas. Anas bin Malik died in the year ninety-three, and Saeed bin Musayab died two years after him, in the year ninety-five." End of quote.