Abu Hurairah (RA) reported Allahs Messenger p. b. u. has saying: All the people of my Ummah would get pardon for their sins except those who publicise them. And (it means) that a servant should do a deed during the night and tell the people in the morning that he has done so and so, whereas Allah has concealed it. And he does a deed during the day and when it is night he tells the people, whereas Allah has concealed it. Zuhair has used the word jihar for publicising.
[Sahih Muslim Hadith # 7845]