According to O Fuxico, a Brazilian gossip website, Katy Perry has criticized Madonna suggesting that the Queen of Pop's concerts are usually blasphemies. Devout Christian, whose parents are pastors, Perry attacked M for using biblical symbols for dramatic effect on stage.
According to Katy, Madonna is a celebrity most offensive quotes to that effect and the cross used by the pop star in her Confessions tour in 2006, where M is "crucified" on stage.
"For me, spirituality and something very important, i do not like when people do not take it seriously. I do not understand why there are artists who play this game, like Madonna on a cross to sing. "
Perry has also asked her husband Russell Brand who take  the religious references out when she performs live.
"Russell has done very blasphemous jokes in the past but is now declining because I know I'm very sensitive about that matter." 

 Source: o fuxico.com http://ofuxico.terra.com.br/arquivo/noticias/2011/01/18/katy-perry-critica-madonna-por-usar-referencias-biblicas-em-shows-95751.html