Sahih Muslim | Book 33 | Hadith Number 6408

Narrated by Sahl b. Sa'd
Sahl b. Sa'd reported it from Allah's Messenger (may peace be upon him) that a person performs deeds like the deeds of the people of Paradise apparently before people and he would be amongst the dwellers of Hell and a person acts apparently like the people of Hell, but (in fact) he would be among the dwellers of Paradise.