It is usually contended that the quantum theory of fields is intrinsically divergent. The present paper attempts to show that this divergence is due to the perturbation theory generally employed and not to the field theory itself. By means of a minor modification in the perturbation calculations, the divergent integrals may be given appropriate finite values. Although there are many apparent ambiguities in field theory, these are ambiguities of representation, and not ambiguities in physical content. The self-energy and stress of particles are zero. The expectation value of the energy momentum tensor for the true vacuum state is zero. From this point of view the polarization of the vacuum and charge renormalization seem to be factitious.