Portraiture

Van Eyck presented himself as an innovator, or trend setter, of his times. Along with mastering the use (not inventing, like originally thought) of oil paints in his workshop, going on secret missions for Dukes, being a Realist (vs. a Nominalist),  he was also the only one of his time to paint secular portraits. 

These occurrences, the depiction and subsequent "immortalization" of the subject at hand without any ties or references to the church of Christianity, were most likely due to van Eycks' ties to the court. His popularity, at that, can also be attributed to his being in the service of Philip the Good.  Eyck's stylization was structured around the tastes and likings of the people he was commissioned by, which takes away from individual expression.