If you follow international news you’ve heard of the plight of an ethnic minority in Iraq called the Yazidis. The Yazidis have been the target of the Sunni radicals who are fighting against the Iraqi government. The Yazidis are being persecuted by the Sunnis because of their religious beliefs. The Yazidis practice a version of Zoroasterianism.

Even if the name Zoroasterianism is unfamiliar to you, the religion is familiar. The Magi in Matthew’s Gospel, who followed the star in order to worship the infant Jesus, were Zoroasterians. The Magi belonged to a caste of highly educated religious leaders who provided counsel to the Persian emperors. The religion of the Yazidis is a mixture of Zoroasterian and gnostic beliefs.

The Yazidis believe in a god who created the world, and then left the world completely in the hands of lesser beings, both human and angelic. The god in their mythology is not directly involved in the events of world history. In order to accomplish good for the world, their god relies on human beings (and angels), to take the initiative to perform good actions and oppose evil.

Yazidi mythology infuriates the Sunni extremists fighting in Iraq. From their point of view, a religion that teaches that humans are necessary in order to accomplish the divine will is a false religion. I mention this to you as an introduction to the Scripture readings this Sunday, which speak about the relationship between God’s will and human will.

In today’s Gospel reading Jesus said to Peter, “I will give you the keys to the kingdom of heaven. Whatever you bind on earth shall be bound in heaven; and whatever you loose on earth shall be loosed in heaven.” (Matthew 16: 19) This brief conversation between Jesus and Peter provides a good illustration of how Judaism and Christianity understand the relationship between God’s sovereignty and human free will.

Christianity and Judaism believe in a God who is above the world and beyond human comprehension. The technical term for this is “transcendent”; “transcendent” in Catholic theology means not being limited by the laws of nature and the vagaries of time. This image of God is expressed in the second reading today. St. Paul quoted the prophet Isaiah when he wrote, “For who has known the mind of the Lord, or who has been his counselor?” (Romans 11:34)

We believe that God is transcendent, above the world; we also believe that God is deeply concerned with the course of world events and intimately involved in the lives of believers. When Jesus entrusted to Peter the “keys to the kingdom of heaven” he was acknowledging the place that human actions have in the working out of God’s will. As the Scriptures remind us, God’s will cannot be thwarted by human effort, the power of evil or unbelief; God will accomplish God’s will regardless of historical circumstances.

At the same time, there is available to every person the blessing of cooperating with God’s will. When Jesus entrusted the future of his work to Peter and the Eleven he was offering them the blessing of being included in God’s plan to redeem the world. Today’s first reading illustrates the same principle, but from a different perspective. The untrustworthy and unfaithful Shebna was deposed and replaced by a leader who would be faithful to God.

Catholicism preserves both God’s sovereignty and human free will by affirming that the relationship between them does not compromise either. God offers believers the opportunity to cooperate with the Divine will, but God does not need human cooperation to accomplish the plan of salvation. Similarly, human freedom is not diminished by cooperating with God’s will; rather, human freedom finds ultimate fulfillment in choosing freely to cooperate with Grace.

Peter, and the Eleven, were offered the blessing and opportunity of both finding fulfillment for human desire and fulfilling God’s will by continuing Jesus’ work of announcing the Kingdom of God. Because of the faith of the apostles, and by virtue of baptism, every believer has a share in the apostolic mission. Not all of us are called to be preachers; not all are called to be missionaries; not all are called to heroic virtue, but all of us are called to participate in Jesus’ work.

Peter is a brilliant example of the type of person who is well-suited to ministry in the Church. He was flaky, unreliable and had a faltering faith. He betrayed Jesus by denying that he knew him. After all of his failures and betrayal he still clung to the belief that he was redeemable and that Jesus might still love him. Those who consider themselves to be sinless and faultless are the ones who feel they deserve to be involved in Church; those who know themselves to be sinners are the ones Jesus calls to be involved in his work.

Participating in Jesus’ work is a necessary consequence of faith. Last Sunday, the Canaanite woman offered an example of faith as a tenacious attachment to Jesus; she was so tenacious and attached that the apostles were threatened by her. This Sunday, we see the results of such a faith: it promotes attachment to Jesus in others, and encourages others to the life of faith.

The “keys to the kingdom” open doors, literally. Keys let some in, and keep others out. The person with the keys manages the household. Each of us has an obligation to participate in the management of Jesus’ ministry. All are invited; those who accept become responsible to invite others. It is common to think of “cooperating with Grace” as a personal effort aimed at securing one’s own salvation. Cooperating with God, however, also has a very public dimension. We who have been admitted to the Kingdom have the sacred responsibility of inviting others to join the company of the saved.

You might not feel led to a position of leadership in Church ministry, but each person has an indispensable role to play in continuing Jesus’ work. God is calling each person here to take some share in the responsibility for that work, and as in the case of Peter, that call comes in the midst of your regular, daily activities. Like the Canaanite woman in last Sunday’s Gospel, we expect God to hear and answer our prayers. God also has expectations of us. As in Peter’s case, Jesus calls each believer to take shared responsibility for the work of announcing God’s Kingdom.