  This paper provides a brief overview of the formation of stellar fossil
magnetic fields and what potential instabilities may occur given certain
configurations of the magnetic field. In particular, a purely magnetic
instability can occur for poloidal, toroidal, and mixed poloidal-toroidal
axisymmetric magnetic field configurations as originally studied in Tayler
(1973), Markey & Tayler (1973), and Tayler (1980). However, most of the
magnetic field configurations observed at the surface of massive stars are non-
axisymmetric. Thus, extending earlier studies of the axisymmetric Tayler
instability in spherical geometry (Goossens, 1980), we introduce a formulation
for the global change in the potential energy contained in a
convectively-stable region given an arbitrary Lagrangian perturbation, which
permits the inclusion of both axisymmetric and non-axisymmetric magnetic
fields. With this tool in hand, a path is shown by which more general stability
criterion can be established.
