Help with a Law Case plz?

Griffin Grimbly a 12 year old boy was beaten by his dad Mr. Grimbly with a length of a nylon clothesline. Police arrested him and charged him with ault. At trial he revealed he was a christian and followed the biblical injuction on child rearing "spare the rod and spoil the child. His laywer cited s. 43 of the criminal code that gives the right to use "reasonable force" in disciplining their children. Decide if hes guilty or not of ault.