He was studying to be a lawyer when he was caught in a thunderstorm. It was quite the storm, or at least we can assume it was, for he prayed to Saint Anne, a fictional character, supposedly the mother of the Virgin Mary, to intervene. He vowed to enter the monastery if he lived, and he did live to tell the tale, and the rest, as they say, is history. This coming Halloween will mark the 500th anniversary of Martin Luther’s defiantly nailing his theses against the sale of indulgences to the door of a church in Wittenberg, often used to post notices, though the original doors are long gone, burned by invading French troops during the Seven Years War.

In 1522, five years after Luther’s defiant act and four hundred and sixty seven miles to the south, in Zurich, another religious revolution would develop, or maybe an offshoot of Luther’s, it is hard to tell. If Luther’s reform can be said to have started with 95 theses, the Zurich reform can be said to have started with, of all things, a sausage. That sausage was boldly and publicly consumed during Lent, a violation of Roman church discipline, an intentional provocation.

In defending this delicious dietary violation by his friends, Pastor Huldrych Zwingli set in motion the Reform tradition from which Congregationalism would eventually spring. While Luther was an academic, Zwingli served as a pastor, placed people above ideas, and had experience as an Army chaplain. This latter role made him an outspoken opponent of war, ironic, since he would die on the battlefield defending his reformation from Swiss Catholic cantons. But there was a second battle going on in Zurich, not with the Roman pope and his armies, but between differing versions of the reform.

Zwingli had challenged the notion of sacrament, the idea that acts like communion and baptism, mediated by a priest, changed the soul. Instead, Zwingli claimed that the soul was changed by the direct action of God, sacraments merely outward signs of that inner transformation. This ultimately led to the breach with Luther, the two strains of the Reformation divided over the nature of communion, over the notion of transformation and sign. Zwingli’s view, still the dominant theology in our tradition, is that the bread is still bread and the wine is still wine, symbols of flesh and blood not substance.

Some of his supporters followed Zwingli’s reasoning to what seemed an obvious conclusion, arriving at an idea called believer’s baptism. Believer’s baptism, though still tied to God’s grace, is an outward sign of an internal transformation, and therefore must be freely chosen by the adult believer who has been transformed as an act of will. This is the opposite of infant baptism, a practice that has no scriptural warrant and is justified by a troublesome theology, the notion of original or hereditary sin. But infant baptism was also tied to a good intention, that of inclusion in the community. Quite apart from wretched theology, it was a mark of belonging.

Zwingli, like Luther and the pope, believed in the civic church, so all citizens were to be included in one single church, the church of the monarch, or in the case of Zurich, of the council. Those who were not part of the civic church were effectively non-citizens, aliens like Jews and Muslims. The battle between Christian movements was not about diversity, for diversity was not valued, but about which version of Christianity would rule in a particular state. The pope, Luther and Zwingli all saw believer’s baptism as divisive, for some in the community would be in, some would be out.

The radicals who supported believer’s baptism came to be called anabaptists, because they re-baptized people who had been baptized as infants. They were persecuted by the Zurich authorities. Four anabaptists were executed by drowning in the River Limmat, a cruel mockery of their belief. To this day, re-baptism is considered anathema in most branches of Christianity, so much so that the United Church of Christ and the Roman church accept one another’s baptisms as legitimate.

The question posed by the conflict between state churches and the Anabaptists was this: Were you a Christian, and a particular type of Christian, as an accident of birth, as part of your ethnic and political identity, because you belonged to this prince or that state, or were you a Christian, and a particular type of Christian, by choice? Religious identity and state identity were mostly co-mingled, much as they are by many theocratic regimes today, places like Iran and Turkey, and co-mingled by some in the United States who long for a theocratic regime, who claim that this must be a Christian nation, that one politician or another is God’s anointed.

This co-mingling of the Christian faith and state authority is referred to as Christendom, appropriately combining the words Christian and kingdom.

It is true that Jesus declared that the kingdom of God was breaking into the world, but even that dramatic divine intervention was opt-in. This is critical, for there was never one Hebrew faith. The authors and redactors of the biblical texts put tremendous effort into creating one consistent narrative, and fail completely, for even the untrained can see the chaos in the story, see differing accounts, differing understandings of the divine.

There were competing sects, and while you might well choose the movement into which you were born, especially if you were born into the privileged priesthood, you could also opt-in to a new movement, the Hasidim, the Pharisees, those folks gathered around John in the wilderness. The Hebrew faith was a hothouse of creativity and innovation, not a monolithic authoritarian faith. The notion that there was a single way to be Hebrew, so deeply embedded in Christian thought, is as wrong-headed as the notion that there is one way to follow Jesus.

We see the opt-in nature of the Jesus movement, a movement that attracted sinners, the unclean, even Pharisees, throughout the texts, invitation, not demand. Jesus lets people walk away. He even lets righteous people walk away. In this, he follows the model of John the Baptizer, who also preached an opt-in kingdom. The key difference is that John preached a closed repentance community, while the community of Jesus seems best exemplified in the radically open table fellowship, creating the basis for the expansion of the faith to the Gentiles.

All of this brings us back to a single question, a terrifying question. What is a Christian? Is being a Christian opt-in, a decision? Are you a Christian because you choose to be one? Because you say you are one? Because you were born into a particular context of Christendom?

Christian as ethnicity seems to be the prevailing understanding of Christian in our time, even within Mainline Protestant churches like ours. Christian is a no cost, no obligation label, meaningless except in that it allows one to identify oneself with power and privilege in which to be explicitly non-Christian is to be the other, Jew, Muslim, Atheist, Mormon, subject to discrimination and abuse. Even that most outward sign of Christian identity, church membership, is reduced to empty words.

And I’d like to suggest that this way of understanding Christianity has nothing to do with Jesus, that God’s grace is direct and universal, but it is opt-in, that the Way of Jesus, declared in the words “I am the way,” is opt-in. It is not a birthright or a splash of water on the head of an infant.

The Way of Jesus is about what you do. In that, it is a discipline like other disciplines, an art like other arts. It requires instruction and practice, changes how we see the world, how we see ourselves, how we interact with others, how we organize our society. The Way is a path, not a random wandering, and while we are a big tent denomination, there are still things we believe. We simply choose to emphasize love, justice and mercy instead of legalism and damnation.

There is structure to following on the Way. It requires commitment, practice, discomfort. We can accept the structure, practice and discomfort of yoga, know that it takes effort to learn Mandarin, understand that going vegan is going to take a lifestyle change. Surely we can bring the same attention and effort to the work of the soul.

The Roman church, possibly the worst offender when it comes to Christendom, to authoritarian monolithic Christianity, is nonetheless responsible for many of the systems for the communal practice of Christian discipleship. One of the best known originated in Spain the same year Zwingli was embracing the sausage rebellion. The Spiritual Exercises of Ignatius of Loyola, the basis for the Jesuit movement of Catholic priests, educators and brothers, including the current Roman pope, was originally a retreat leader’s handbook, in which those on retreat spent four weeks in silence and solitude learning how to discern the will of God. It has been adapted many ways, including forms more acceptable to lay Christians and Protestants. The young actor Andrew Garfield recently completed the exercises in preparation for a role, and has spoken publicly about the profound impact the discipline has had on his life.

The key to the Spiritual Exercises is that they are done under the auspices of a spiritual director, not only a source of experience and wisdom, but also a source of accountability, for we know how easy it is to give up, slack off. As scripture reminds us, the spirit may be willing, but the flesh is week. And there are a dozen emails to answer, and the smartphone is buzzing, and there is always tomorrow. Except when there isn’t.

Another system of the Roman church, also from Spain, first appeared as the Second World War was drawing to a close. Designed to develop lay leaders, it was called Cursillos de Christiandad, or Short Course in Christianity. It begins with a three day retreat in which they teach a method, which leads to the “fourth day,” the rest of your life. It is built on the foundation of piety, study and action, and a system of accountability.

Arms and chest on Monday, Wednesday, Friday. Legs and back on Tuesday, Thursday, Saturday. This or some other pattern, which lifts, which pulls., don’t forget your squats Everyone who has a fitness routine has a fitness routine. We may adapt and deviate, but we are willing to accept structure in our lives, know that we get a better workout when we have a partner to push us.

The cursillo method works because of accountability, because there are workout partners. Every week, cursillistas, as participants are called, are expected to sit down with two to four others in a small group to account for their piety, study and action in the previous week, to commit to specific practices of piety, study and action for the coming week, which they will report on a week later.

The cornerstone of our faith is relationship, our relationship with the divine through the story of the Hebrew tradition, our relationship with what the German theologian Friedrich Schleiermacher called the “perfect Christ-consciouness” experienced in Jesus, our relationship with one another as voluntary participants in an ongoing and incomplete Jesus revolution. And relationships involve reciprocity, mutuality, and most of all, accountability.

Jesus tells us that “whoever believes in me will do the works that I do.” “What would Jesus do” may today be the rallying cry of a heretical fundamentalism, but it originated in a progressive movement, the social gospel. What Jesus would do is terrifying and hard and way bigger than any of us alone. The Way of Jesus takes discipline and effort, teachers and coaches, pain and fatigue. It takes a sure foundation, courage. It takes us all.

We have dressed “consumer church” up as “free church,” but church is not church if it is not accountable to Christ, if people on the Way are not accountable to one another.

When was the last time you lovingly held someone accountable? When was the last time you asked someone else about their prayer life? Even sitting down with a person when our relationship is strained is difficult these days. Few can do it. Instead, we talk in the parking lot, call and complain to others, or simply abandon relationships altogether, walking away from covenant, from the messy work of love.

We must build relationships of trust, then adopt methods, hold one another accountable, make church into a school of discipleship so that we are on the Way every day, even the days when we don’t want a spiritual workout.

If we do this, our faith will not be about an hour a week, and our work of changing lives, of creating a world that reflects the radical goodness of God, will become a reality, because the work of faith will not be done by the church, an institution that sits on a plot of land, but by the church, a people on the Way and in the world.

Look around. Your spiritual workout partners are sitting in this room. Create a routine. Hold each other accountable. Let’s change the world.