Blessed chalk will be available at all Masses this Sunday, 5th January, for the traditional Epiphany house blessing.
It is the custom to use the chalk to mark the lintel above your front door, or a space nearby, in this way:
20 + C + M + B + 20
The year and the crosses are easy to understand. The three letters either stand for the traditional names of the Wise Men (Caspar, Melchior and Balthasar) or the Latin Christus mansionem benedicat (May Christ bless this home) a prayer you can say as you mark the doorway.