As for those who enjoin the good and forbid the evil for other purposes like showing off or to be heard or a worldly significance or for any other reasons or even to oppose the act of enjoining the good and perpetrating the evil then they are the filthiest of mankind and from the evilest who will face a severe consequence. And in the two Saheeh [authentic collections of prophetic narrations] from Usaamah bin Zayd from the Prophet r that he said: “A man will be brought forward on the Day of Resurrection and thrown in the hellfire. The insides of his stomach will be hanging out. He will circle around the hellfire the same way that a donkey circles around the grain grinder. The people of the hellfire will gather around him and say, “What has happened to you O such and such person? Did you not used to enjoin the good and forbid the evil?” And he will say to them, “Certainly but I used to command you to enjoin the good but not do it myself and I would forbid the evil amongst you and fall into it myself.”
Other Sources:
Words of Wisdom by Luqman (from Quran and Sheikh Ibn Kathir's Book)
