The following is an excerpt from chapter 34, from the book The Winter Pascha, by Fr. Thomas Hopko as found on the Antiochian Orthodox Church website.

The rite of the Great Blessing of Water is celebrated in the Orthodox Church after the vesperal divine liturgy on the eve of the feast of the Epiphany [Theophany], and after the eucharistic liturgy on the day itself. It begins with the chanting of special hymns with the incensing of the water, and concludes with bible readings, petitions and prayers.

Today the nature of the waters is sanctified,
The Jordan bursts forth and turns back the flood of its streams,
Seeing the Master wash Himself.

To the voice of one crying in the wilderness,
Prepare ye the way of the Lord,
You came, O Lord, taking the form of a servant,
Asking for baptism though you have no sin.
The waters saw You and were afraid.
The Forerunner began to tremble and cried out, saying:
How shall the lampstand illumine the Light?
How shall the servant lay hands upon the Master?
Sanctify both me and the waters, O Savior,
Who takes away the sins of the world.1

.....

God has sent His only-begotten Son "not to condemn the world, but that the world might be saved through Him." (Jn 3:17) He has sent the Lord Jesus Christ not only to save people's souls, but to save their bodies, and not only to save human beings, but to save the entire creation.

You are great, O Lord, and Your works are wondrous, and there are no words capable of hymning Your wonders... For of Your own will You brought all things in to being from nothing, by Your power You uphold the whole of creation, and by Your providence You order the world... The sun sings to You, the moon glorifies You, the stars meet together before Your face, the light obeys You, the deeps shudder before You, the water springs serve You... We confess Your grace, we proclaim Your mercy, we conceal not Your gracious acts: You have set free our mortal nature. By Your birth You have sanctified the Virgin's womb. All creation sings praises to You Who have revealed Yourself. For You, our God, have appeared upon earth and have dwelled among men. You have sanctified the Jordan streams... Therefore, O Master, be present here now by the descent of the Holy Spirit, and sanctify this water. Give it the blessing of Jordan. Make it a fountain of incorruption, a gift of sanctification, a remission of sins, a protection against disease, a destruction of demons... and may it be for those who will partake of it, to the cleansing of their souls and bodies, to the healing of their passions, to the sanctification of their homes, to every expedient purpose...2

Since the Son of God has taken human flesh and has appeared in the world, manifesting Himself in His baptism in the Jordan, all flesh and all matter is sanctified. Everything is made pure and holy in Him. Everything which is corrupted and polluted by the sinful works of men is cleansed and purified by the gracious works of God. All death-dealing powers of the devil which poison the good world of God's creation are destroyed. All things are again made new. Through the "prime element" of water on the feast of the Epiphany the entire creation is shown to be sanctified by God's Word through the same Spirit of God who "in the beginning... was moving over the face of the waters." (Gen 1:2)

Come, O ye faithful,
Let us praise the greatness of God's dispensation toward us,
For He who became Man because of our transgressions
And who alone is clean and undefiled,
Was for our cleasing Himself cleansed in the Jordan
That He might sanctify both me and the waters...
Let us then draw water in gladness, O brothers,
For upon those that draw in faith
The grace of the Spirit is invisibly bestowed by Christ
The God and Savior of our souls.3

1Opening hymns from the rite of the Great Blessing of Water.
2The Main Prayer from the rite of the Great Blessing of Water.
3Concluding Hymn from the rite of the Great Blessing of Water.