In the Book of Genesis, we read that creation began when the Spirit of God moved over the face of the waters. (Gen. 1:2) Throughout the Bible, water plays an important and a 'mystical role' in human existence and in man's relationship with God the Creator.
Water has the capacity to produce death, as recounted in the story of Noah and the ark (Gen. 6); or to produce life, as noted in the story of Moses' striking the rock in the desert to produce water for the parched wanderers (Numbers 20). While the waters of the Red Sea parted to allow the Hebrews to pass over in safety (and thus preserve life), the same waters came rushing upon the Pharoah and his army drowning them.
In the New Testament, we see water becoming the means by which the Trinity was revealed during the Baptism of Jesus, which we celebrate on the Feast of Theophany on January 6 each year. In the Baptism of Jesus, at the hands of John the Baptist, the spiritual significance and potential of water as the source of life is again revealed and reaffirmed just as in Genesis, the first book of the Bible.
In a sermon on Theophany, St. John Chrysostom says: "On this day Christ was baptized; through His Baptism He sanctified the element of water. There let us all draw of the water and store it in homes, because on this day the water is consecrated."
In blessing water on the Feast Day, we ask and pray that the original purpose of water, as a source of life, blessing and holiness be revealed to us as we drink it. In the Garden of Eden, Adam enjoyed a unique and lordly relationship with Creation. After the Fall as he was expelled from Paradise, he heard the words, "Cursed is the ground for thy sake; in sorrow shalt thou eat of it all the days of thy life." (Genesis 3:17) From that point Adam would be subject to Creation, and not a master. Yet through Christ, the curse is lifted, just as the curse of death is lifted from the human race through the Resurrection. Because of Christ's coming and His work of salvation and redemption (as the hymns say, "dispensation"), Man and Creation are reconciled. Creation is able once more to meet not only the physical needs of man, but the elements of creation can be, and are, sources of grace and healing as we worship the Lord of Life.
When we bless water - or any other material object - and when we celebrate the Mysteries (Sacraments) of the Church, we reverently and gratefully proclaim that Christ Himself (in the words of the Divine Liturgy) "offers and is offered" blesses and sanctifies the world (cosmos) as the Great High Priest.
The celebration of the Great Blessing of Water is an affirmation that through Christ's own baptism, He who is our loving Lord has lifted the curse of Adam's sin, and given the creative goodness of God's creation back to mankind once again.