From The Celtic Daily Prayer:
Christ, as a light
illumine and guide me.
Christ, as a shield
overshadow me.
Christ under me;
Christ over me;
Christ beside me on my left and my right.
This day be within and without me,
lowly and meek, yet all-powerful.
Be in the heart of each to whom I speak;
in the mouth of each who speaks unto me.
This day be within and without me,
lowly and meek, yet all-powerful.
Christ as a light;
Christ as a shield;
Christ beside me
on my left and my right.
Amen.