  We provide a description of the excursion measure from a point for a
spectrally negative L\'evy process. The description is based in two main
ingredients. The first is building a spectrally negative L\'evy process
conditioned to avoid zero and the study of its entrance law at zero. The latter
is connected with both the excursion measure from zero of the process reflected
in its infimum and reflected in its supremum. This lead us to establish a
connection with the excursion measure from the state zero with the excursion
measure from zero for the process reflected at the infimum and reflected at the
supremum, respectively, which is the second main ingredient of our description.
