EWTN.com - Consecration of Bread and Wine: "Consecration of Bread and Wine
At what point during the Eucharistic Prayer is the bread and wine consecrated and converted to the Body and Blood of Christ? Is it when the priest says, 'Let your Spirit come upon these gifts .....', or when he says, 'this is my body....., this is the cup of my blood'?
Answer by David Gregson on 11/7/2008:
The traditional position of the Catholic Church is that the conversion of elements (bread and wine) takes place at the words of consecration, 'This is my Body...,' 'This is the Cup of my Blood...' The Eastern Church has traditionally held that the consecration takes place at the Epiclesis, the invocation of the Holy Spirit, which in Orthodox liturgies takes place after the words of consecration. In order to avoid controversy on the issue, the new eucharistic prayers, composed for the reformed liturgy after Vatican II, placed the Epiclesis before the words of consecration. That way there could be no question that the transubstantiation had taken place by the time the words of consecration had been spoken."