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Epiphany of Our Lord (1st Class Feast).

Fr. Mark, "Epiphany Blessing: Christus mansionem benedicat" (Vultus Christi, January 6, 2010), writes:

For those of you who keep the Epiphany of the Lord on the traditional date of January 6th, and for those of you who haven't yet blessed your houses for the Epiphany, here again is the traditional blessing from the Roman Ritual with a little explanation of it.

Epiphany Inscription Over the Doorway of the Home

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The letters have two meanings. They are the initials of the traditional names of the Three Magi: Caspar, Melchior and Balthasar. They also abbreviate the Latin words Christus mansionem benedicat. May Christ bless the house.” The letters recall the day on which the inscription is made, as well as the purpose of blessing.

The crosses represent the protection of the Precious Blood of Christ, Whose Sacred Name we invoke, and also the holiness of the Three Magi sanctified by their adoration of the Infant Christ.

The inscription is made above the front door, so that all who enter and depart this year may enjoy God's blessing. The month of January still bears the name of the Roman god Janus, the doorkeeper of heaven and protector of the beginning and end of things. This blessing "christens" the ancient Roman observance of the first month. The inscription is made of chalk, a product of clay, which recalls the human nature taken by the Adorable and Eternal Word of God in the womb of the Virgin Mary, by the power of the Holy Spirit.

To bless your home this Epiphany, first read the Prologue of Saint John's Gospel, followed by the Our Father, and the Collect of the Epiphany; then write the inscription for this year above your front door with blessed chalk.

Related:

For more on this, see our post, "The Blessing of Epiphany Water & Chalk - Part 1 of 2" (Musings, January 3, 2010).