Second Day within the Octave of the Immaculate Conception
The most important feasts of the Virgin are the Assumption and the Immaculate Conception, both of the first class and with an octave. That is why each day the Creed is said, that profession of faith fixed at the Council of Constantinople which was only chanted when the attendance in church was very large.
Let us prepare for the birth of Christ in our hearts by adorning them with a little of His mother's purity.
Gaudens gaudébo in Dómino, et exsultábit ánima mea in Deo meo: quia induit me vestiméntis salútis; et induménto justitiae circúmdedit me, quasi sponsam ornátam monílibus suis. Ps. Exaltábo te, Dómine, quoniam suscepísti me: nec delectásti inimícos meos super me.
I will greatly rejoice in the Lord, and my soul shall be joyful in my God: for He hath clothed me with the garments of salvation, and with the robe of justice He hath covered me, as a bride adorned with her jewels. Ps. I will extol Thee, O Lord, for Thou hast upheld me: and hast not made my enemies to rejoice over me.
(Isaias 61:10 and Psalm 29:2 from the Introit of Mass)
Deus, qui per immaculátam Vírginis Conceptiónem dignum Fílio tuo habitáculum praeparásti; quaesumus, ut qui, ex morte ejúsdem Fílii tui praevísa, eam ab omni labe praeservásti, nos quoque mundos ejus intercessióne ad te pervenire concédas.
O God, who by the Immaculate Conception of the Virgin didst prepare a worthy dwelling place for Thy Son: we beseech Thee, that as by the foreseen death of the same Thy Son, Thou didst preserve her from all stain, so Thou wouldst grant to us also, through her intercession, to come unto Thee with clean hearts.
From the Catholic Encyclopaedia on the Immaculate Conception: http://www.newadvent.org/cathen/07674d.htm
Meditation for 9th December from Bishop Challoner: http://www.liturgialatina.org/challoner/dec7.htm#9