Septuagesima is the two and a half weeks leading up to Ash Wednesday and the beginning of Lent. With the exception (if it should fall in this time) of February 2nd, the Feast of the Purification of the Blessed Virgin Mary, which is officially the end of the Christmas Cycle, the liturgical emphasis ceases to be upon the joys of Christ's birth giving way to the realization of why He came to the earth and the heavy price the Christ Child will have to pay to redeem us.
The season of Septuagesima is therefore a preparation for Lent. It serves as a time of transition, a liturgical “buffer” for the soul which must pass from Christmas Joys to the stern penance of the sacred forty days. Liturgically we see the white vestments of Christmas and Epiphany, a color of joy change to the penitential color of violet. We shall also notice the absence of the Gloria on Sundays and ferial days of the season as well as the suppression of the joyful alleluia whenever it occurs in the liturgy. This season of Septuagesima invites us to begin thinking about what we are going to give up and what we are going to do positively (prayers, alms, good works etc.) during the coming Lent for the love of Our Lord who has suffered so much for love of us! Let us prepare now in order to make the best Lent ever!
Taken from Notes Made at the Conferences of Dom Prosper Guéranger)
Et ex Patre natum, ante omnia saecula, born of the Father before all ages. Ages began only when God sent forth Creation from His hands; that ages might be, time must needs exist, and that time might be, created beings were necessary. Now, before all ages, before aught had yet stepped forth from nothingness, the Son of God had issued from the Father, as we here confess in these words: Ex Patre natum ante omnia saecula. Deum de Deo, lumen de lumine, Deum verum de Deo vero [God from God, light from light, true God from true God]. The created world proceeds from God, because it is His handiwork; but for all that, it is not God. The Son of God, on the contrary, coming from the Father, is God as He is, because Begotten by Him: in so much, that all that is said of the Father befits the Son, save only that He is not the Father; but He is ever the same Substance, the same Divine Essence. But still, how can the Son be the same substance as the Father, without this Substance becoming thereby exhausted? St. Athanasius, speaking on this subject, gives us the following comparison, which, although material, enables us, in some measure, to seize this Truth. In the same manner, says he, as a torch lighted from another of the same substance, in no way lessens that from which it is lighted, so also the Son of God, taking the Substance of the Father, in no way diminishes this Divine Substance which He shares with Him; for He is in very deed, God of God, Light of Light, True God of True God.