Throughout the show, it's being said numerous times that the older a vampire is, the stronger they get. And especially Godric, who is said to be the strongest vampire that exists.
However, Godric himself says:
It won't take long, at my age
Referring to how long it will take the sun to burn him. This contradicts the fact about being stronger, as it would be expected a strong vampire will take longer to be destroyed.
How can this inconsistency be explained, if at all?