gistfile1.txt

////in questions#create action

 if filter_profanity( @question.body, I18n.t(:bad_words).split( /, */ ) ).present?
   redirect_to @question, :alert => I18n.t(:bad_words_warning) and return
 end


///in the application controller

 def filter_profanity( check_str = "", prohibited_words = [] )
   return check_str.downcase.gsub!(/[^a-z]/, " ").split(" ").uniq.map { |w| w if prohibited_words.include?( w )  }.compact!  
 end