Both mysticism properly so called and practical asceticism owe valuable works to his pen .
Dionysius the Carthusian is esteemed as a highly gifted teacher of the spiritual life .
Both mysticism properly so called and practical asceticism owe valuable works to Dionysius the Carthusian 's pen .
Dionysius the Carthusian is esteemed as a highly gifted teacher of the spiritual life .