  The tearing mode instability is one important mechanism that may explain the
triggering of fast magnetic reconnection in astrophysical plasmas such as the
solar corona and the Earth's magnetosphere. In this paper, the linear stability
analysis of the tearing mode is carried out for a current sheet in the presence
of a guide field, including the Hall effect. We show that the presence of a
strong guide field does not modify the most unstable mode in the
two-dimensional wave vector space orthogonal to the current gradient direction,
which remains the fastest growing parallel mode. With the Hall effect, the
inclusion of a guide field turns the non-dispersive propagation along the guide
field direction to a dispersive one. The oblique modes have a wave-like
structure along the normal direction of the current sheet and a strong guide
field suppresses this structure while making the eigen-functions asymmetric.
