"The New Encyclopedia of Islam" also states that after the early period, with some notable exceptions, the practice in Islam regarding atheism or various forms of heresy, grew more tolerant as long as it was a private matter. However heresy and atheism expressed in public may well be considered a scandal and a menace to a society; in some societies they are punishable, at least to the extent the perpetrator is silenced. In particular, blasphemy against God and insulting Muhammad are major crimes.