In this passage Isaiah denounces one Shebna, the prime minister (“who is master of the household,” Is 15), and predicts his replacement by Eliakim. The passage is notable for its use of the “key” taken up in the Gospel today, the Tu es Petrus saying.
Responsorial Psalm: 138:1-2, 2-3, 6, 8
Slightly different selections of verses from this psalm are used on
the fifth and seventeenth Sundays of the year in series C. Today’s
refrain (“Lord, your love is eternal”) suggests that God’s purposes
are not defeated by the infidelity of his human instruments. God can
replace a faithless agent with another who is faithful to him.
This magnificent doxology comes at the end of Paul’s
discussion of Israel’s place in salvation history. Biblical
theology is an attempt to reflect on the ways of God in salvation
history. This is precisely what Paul has been doing in Rm 9-11.
But the biblical theologian must always confess the inadequacy of
his or her work.
The riches and wisdom of knowledge of God are always too deep to
penetrate, God’s judgments and ways are unsearchable. No
theologian has ever known the mind of the Lord. No theology, however
venerable, can claim to be absolute.
There comes a time when the theologian must lay down the pen and
confess the relativity of all his or her formulations. Theology is
therefore always subject to change. And theology is best done in the
context of liturgy. It must be doxological.
Matthew has introduced considerable alterations into his Marcan
source. The words “Son of the living God” are added to
Peter’s confession. In Mark, Jesus almost ignores
Peter’s confession and enjoins the disciple to silence. He
then proceeds at once to speak of the necessity of his passion.
Peter protests and is met by the rebuke “Get behind me,
Satan.”
Matthew has placed the prediction of the passion, Peter’s
objection, and Jesus’ rebuke in a separate pericope following
the confession. Instead, Jesus pronounces Peter blessed and gives
him the name Peter, “Rock.”
Then comes a series of promises: the building of the church on the
foundation of Peter; the assurance that the powers of death shall
not prevail against that church; the promise of the keys; and the
saying of the binding and loosing.
There seems to be a growing consensus that the original situation of
these words to Peter was not in the earthly life of Jesus but in a
post resurrection setting; that the whole passage, Mt 16:17-19, enshrines very early material going back to the Aramaic-speaking
Church; and that the Rock on which the church is to be built is
Peter himself, not his faith, as some patristic and most Reformation
exegesis has supposed.
But there is division among exegetes along confessional lines over
the question of the continuation of Peter’s function in the
church.
Protestant exegesis sees the fulfillment of the saying about the
Rock in the once-and-for-all role that played such a large part in
the foundation of the church after the first Easter and resurrection
appearances (Cullmann), and sees the power of the keys and of
binding and loosing as continued in the church as a whole, though
capable of being entrusted to particular officers by the community
(Marxsen).
Anglican exegetes tend to agree with the Orthodox that the power of
the keys and of binding and loosing is shared by the whole
episcopate, though many of them would be prepared to allow the
Bishop of Rome a special place in this collegial office. Catholic
scholars naturally maintain that the Petrine office is vested in the
papacy.
Nonetheless, it is significant that on all sides there is growing
Christian awareness that one aspect of the Petrine office—witness to
the resurrection—belongs to the events of the Christian beginnings
and is therefore inalienable. At the same time, its other
aspects—keys, binding and loosing—continue in the church. This
continuity is a sign of the faithfulness of God.