Preaching to Others but not Practising Oneself

عن الوليد بن عقبة رضي الله عنه قال قال رسول الله صلى الله عليه وسلم إن أناسا من أهل الجنة ينطلقون إلى أناس من أهل النار فيقولون بم دخلتم النار فوالله ما دخلنا الجنة إلا بما تعلمنا منكم فيقولون إنا كنا نقول ولا نفعل رواه الطبراني في الكبير (الترغيب والترهيب 1/171)

Hazrat Waleed bin Uqbah (Radhiyallahu Anhu) reports that Rasulullah (Sallallahu Alaihi Wasallam) said: “A group of the people of Jannah will go to a group of the people of Jahannum and ask them: ‘What has caused you to enter Jahannum? By the qasm of Allah, we only entered Jannah because of what we learnt from you (i.e. the good we acquired through your preaching to us).’ They would reply saying: ‘Indeed we used to preach and speak about it, however we did not practise upon it (in our lives).’”