It means gift from the lord.
It's a Dutch form of Mathew, Matthew or Mathias.
Usually Matthijs is a very cute but shy boy.
He stands for honor and duty, if you betray him you'll be his worst enemy,
but if you love him he'll always be there for you and will die to protect what he believes is right.
also: finding obscure and funny sites on the internet.
He's Matthijsed a site about penguin conspiracies.