On this day the service of Matins concludes with the solemn veneration of the Precious and Life-Giving Cross; the ceremonies are closely parallel to those at the feasts of the Exaltation of the Cross (14 September) and the Procession of the Cross (1 August). The veneration of the Cross on this third Sunday in Lent prepares us for the commemoration of the Crucifixion which is soon to follow in Holy Week, and at the same time it reminds us that the whole of Lent is a period when we are crucified with Christ: as the Synaxarion at Matins says, ‘Through the forty-day Fast, we too are in a way crucified, dying to the passions.’ The dominant note on this Sunday, as on the two Sundays preceding, is one of joy and triumph. In the Canon at Matins, the irmoi are the same as at Easter midnight, ‘This is the day of Resurrection…’ and the troparia are in part a paraphrase of the Paschal Canon by St. John of Damascus. No separation is made between Christ’s death and His Resurrection, but the Cross is regarded as an emblem of victory and Calvary is seen in the light of the Empty Tomb.
Source: The Lenten Triodion. Mother Mary, of the Monastery of the Veil of the Mother of God, Bussy-en-Othe, and Archimandrite Kallistos Timothy Ware: 1977.