undutiful (adj.)

• apostate
• atheistic
• blasphemous
• disobedient
• fallen
• froward
• impious
• indifferent
• irreligious
• irreverent
• lapsed
• lawless
• lukewarm
• naughty
• nonconforming
• nonobservant
• obstinate
• profanatory
• profane
• recreant
• recusant
• renegade
• sacrilegious
• self-willed
• undisciplined
• violative
• wayward
• willful