  There is a good deal of current interest in the condensate g^2A_\mu^aA_a^\mu>
which has recently be shown to be the Landau gauge version of a more general
gauge-invariant expression. In the present work we consider quark propagation
in the presence of such a condensate which we assume to be present in the
vacuum. We describe the vacuum as a random medium of gluon fields. We discuss
quark propagation in that medium and show that the quark propagator has no
on-mass-shell pole indicating that a quark cannot propagate over extended
distances. That is, the quark is a nonpropagating mode in the gluon condensate.
