What causes wiglaf to come to the aid of Beowulf?

Whereas the others in the company are held by the command of their lord (do not interfere; leave this to me), Wiglaf is full of shame that he has been a retainer for many years, has benefited from feasts and gift-giving, but here at this moment he sees that his lord is dying. By disobeying the given order he proves that he is more faithful to his lord than those who simply obey him.