The homily, on account of its importance and its nature, is reserved to the priest or deacon during Mass.
As regards other forms of preaching, if necessity demands it in particular circumstances, or if usefulness suggests it in special cases, lay members of Christ’s faithful may be allowed to preach in a church or in an oratory outside Mass in accordance with the norm of law.
This may be done only on account of a scarcity of sacred ministers in certain places, in order to meet the need, and it may not be transformed from an exceptional measure into an ordinary practice, nor may it be understood as an authentic form of the advancement of the laity.
All must remember besides that the faculty for giving such permission belongs to the local ordinary, and this as regards individual instances; this permission is not the competence of anyone else, even if they are priests or deacons (161).
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