A Short History of Consecration.
The concept of Consecration, that of setting a person, place or object aside from the material world and dedicating it permanently to the service of God can be traced back to the ancient world. It was known amongst the Egyptians and other pagan peoples. Within our own religious heritage, at the time of Moses we find the concept applying to the whole Jewish people (Exodus, chapter 24) – the act of Consecration involving the erection of an altar and twelve memorial stones, the selection of twelve individuals to perform burnt-offering, the reading of the Covenant and the sprinkling of the people with blood. Within this, we find the same concept applied to Aaron and his sons (Exodus, chapter 29), their investiture by Moses being described in some detail (Leviticus, chapter 8) and including the use of oil for anointing. As with the modern tradition, this ‘setting aside’ was understood to be a permanent act.
Centuries later, we find the came concept recurring again in the Roman world, with the permanent ‘setting aside’ from the secular world of whatever was devoted to the worship of their gods. In the early Apostolic church we find the consecration of churches existing as a continuation, in a sense, of the ancient Jewish rite instituted by Solomon. Although some scholars attribute its origin to Pope St. Evaristus (d. 105), it is probable that he only codified in law what was the common practice at the time. It is certain that churches were formally consecrated before the persecution of the Christian Faith had ended can be seen from the life of St. Cecilia who is known to have prayed for a cessation of hostilities in order that her home may be consecrated as a church by Pope St. Urban I (222-230). We find another mention in the life of St. Marcellus (d. 309) who is thought to have consecrated the home of St. Lucina as a church. After the conversion of the Emperor Constantine (312), what had, out of necessity, been an essentially private ceremony, became a solemn public rite. This can be gathered from the writings of Eusebius of Cesarea (c. 264-340), indicating that churches had been consecrated previously: "After these things a spectacle earnestly prayed for and much desired by us all appeared, viz. the solemnization of the festival of the dedication of churches throughout every city, and the consecration of newly-built oratories".
It is uncertain, in these early times, to know exactly what form the rite of consecration took or even if the rite was identical throughout the Christian world. However, what is clear is that the essential element of the service, that of permanently separating the building from secular to sacred use was already established as part of the Christian tradition.
Sources:
New Jerusalem Bible
The Catholic Encyclopedia
Chambers Biographical Dictionay
David Hugh Farmer – The Oxford Dictionary of Saints