Let all the trees of the wood, planted from the beginning of time, rejoice; for their nature hath been sanctified by the stretching of Christ on the Tree. Wherefore, now, we worship Him, lifted up, and magnify Him.
+ Orthros of the Feast, Tone 8
By the mere planting of thy Cross, O Christ, the foundation of death did shake; for him whom Hades did swallow eagerly, it delivered up with trembling; for verily, thou didst reveal to us thy salvation, O holy One. Wherefore, do we glorify thee, O Son of God. Have mercy upon us.
+ Orthros of the Feast, Tone 6
Today the Church celebrates the feast of the Elevation of the Holy Cross. Two events connected to the Honorable Cross of our Lord are commemorated this day: first, the finding of the Cross by the Empress Helena in the Holy Land; and second, the return of the Cross from Persia to Jerusalem in the year 628.
Historical background of the Feast 
Read a reflection about the Feast on OCN's The Sounding blog 
The Liberating Cross  by Fr. Stephen Rogers
Fr. Thomas Hopko discusses the Feast on Ancient Faith Radio