atheistic (adj.)

• apostate
• atheist
• blasphemous
• disbelieving
• faithless
• fallen
• gentile
• heathen
• impious
• irreligious
• irreverent
• lapsed
• pagan
• profanatory
• profane
• recreant
• renegade
• sacrilegious
• unbelieving
• unchristian
• undutiful