"Hassan is Adonis' tutor and guardian. He is the only one who looks after the boy after the overbearing combat training sessions between Adonis and his father, General Julius. After one particularly intense session, he reassures Adonis that ever since the death of the boy's mother, his father has tried desperately to train him into a knight, and to not resent Julius' actions. He later pleads with Julius to be less intense in his sessions with Adonis, reminding the general that the boy is only thirteen years old and misses his late mother." -wiki discription 

A kind old man, and the voice should reflect that. Think of a loving grandfather sort of performance.