The Responsorial (Deuteronomy 32:3-12) “names” the People of God (who have become the Church) as
God’s special possession! “The portion of the Lord is his People.”
In Deuteronomy 31:1-8 Moses urges the people to enter with confidence into “the land which the Lord swore to their fathers he would give them.” They must not doubt God’s power or his promises: “It is the Lord, your God, who will cross [the Jordan river] before you.”
If we really think of what we are doing, we might hesitate to “cross over” from the Liturgy of the Word into the Eucharistic Prayer. There is a definite passage or transition from what could be understood as very human worship of God into an act of worship beyond all human power or comprehension.
We might experience the Liturgy of the Word as nothing more than listening to words that human authors wrote (although inspired by God), trying with our human intellects to understand them and with our human wills to put them into practice — counting, of course, on the aid of “grace,” understood as some kind of special boost from God. And the Liturgy of the Word is all of this, although it is much, much more.
But when we “cross over” into the Eucharistic Prayer, we find ourselves in another time-frame, united to Jesus in his dying on the cross two thousand years ago, offering ourselves with him and in him for the life of the world, united to his will as we only can be by the gift of sharing in his divine life. Is it surprising that people seldom either teach or reach this level of mystery when explaining or participating in Mass? But we need to do it. And the opening words of the Eucharistic Prayer prepare us for it: “Father, you are holy indeed.” And so are we!
Moses was not allowed to cross over into the Promised Land because he failed to show God’s “holiness” to the People by trusting sufficiently in his power at the “waters of Meribah.” If we hold back from entering fully into the daunting mystery of the Eucharistic Prayer, we are lacking in faith, trust and love. And we will fail to enter into the “Promised Land” of the Mass.
We can only enter fully into the Mass by “being Christ.” Jesus, by making us one with himself on the cross, “became sin” for us “so that in him we might become the very holiness of God.”
Jesus gives us a preview of this mystery in Matthew 18:1-14 when he says we must “change and become like little children.” He is not talking only about a change of attitude, but about being reborn. This is what makes us “greatest in the kingdom of heaven.” Our true greatness comes essentially from the gift of sharing in God’s divine life, by which we “become Christ.” In this sense Jesus said, “The least in the kingdom of heaven is greater” than any human qualities people saw in John the Baptizer. By grace we are “holy” as God is, by his life in us...
Initiative: Listen to the words of the Eucharistic Prayer. Accept their mystery.
 See the full story in Numbers 20: 6-12.
 2Corinthians 5:21, New American Bible, 1970.
 Matthew 11:11. And see Luke 8: 19-21; 11:27-28.