Commentary on Luke 17:5-10
Sometimes discipleship amounts to simple expressions of faithfulness.
Luke 17:5-10 follows Jesus’ stern warning to his disciples concerning causing “little ones” to stumble (17:1-4). The pericope itself contains two sub-units. The first, 17:5-6, involves a quick interchange concerning the apostles’ request for greater faith. This sub-unit concludes with Jesus’ saying concerning mustard seed faith. In the second, 17:7-10, Jesus continues as the speaker, but with an apparent change in topic. Now the emphasis seems to reside with expectations for disciples. Apart from their apparent harshness, these two sub-units share little in common.
Luke has combined a Q saying concerning mustard seed faith (see Matthew 17:20) with Mark’s tradition concerning the fig tree and prayer. Mark’s story dramatizes Jesus’ conflict with the Jerusalem Temple and the authorities who run it.
Have faith in God. Truly I tell you, if you say to this mountain, “Be taken up and thrown into the sea,” and if you do not doubt in your heart, but believe that what you say will come to pass, it will be done for you. (11:22b-23)
“This mountain” refers to the mountain around which Mark’s passion story revolves, the temple mount. Luke retains Mark’s tossing into the sea imagery but removes it from its temple context. In Luke, faith moves a tree, not a mountain. In other words, Luke’s saying applies not to a specific religious and political conflict but to ordinary discipleship and sufficient faith.
Luke’s Gospel sometimes presents discipleship in terms of severe expectations. The would-be disciples of Luke 9:57-62 all seem prepared to follow Jesus. Yet Jesus rebuffs them for various reasons. “Foxes have holes, and birds of the air have nests,” but discipleship is hard stuff. A man wants to care for his father, another wants to say goodbye to his family, but the urgency of discipleship leaves no room for such common expressions of devotion. If one wants to be a disciple, Jesus suggests that one count the cost (14:25-34). The investment is great (like building a tower) and risky (like going to war). You would better consider the sacrifice; after all, “none of you can become my disciple if you do not give up all your possessions” (14:33).
In that light it is no wonder that the apostles desire greater faith (17:5). Jesus has just characterized causing a little one to “stumble” as a fate worse than drowning. “Be on your guard!” he says (17:1-3); that is, “Watch yourselves!” Having encountered such high expectations, and now hearing such a daunting admonition, of course the apostles ask for help.
Yet, Jesus does not offer help, at least not the kind the apostles seek. The Greek syntax of 17:6 implies a criticism of the apostles. The little particle an following “If you had faith the size of a mustard seed,” suggests that the apostles lack even such minimal faith. In other words, Jesus not only declines the apostles’ request, he piles criticism on top of it.
Jesus intensifies our discomfort with his parable concerning slave-owners and their slaves. The parable first invites the apostles to identify with the slave-owners: literally, “Which one of you, having a slave plowing or tending sheep. . . ?” (17:7). We are to imagine a person with resources sufficient to own a slave but not one wealthy enough to assign different slaves to diverse tasks. This poor slave works out in the fields and in the home. The parable shifts focus in verse 10, calling the audience to identify with the slaves. A “good” slave does not expect thanks.
I wish I could offer some intelligent way to mitigate the dangers of the slave imagery in this parable. The story really is about slaves, and it relies upon very conventional expectations of slaves to make its point. Preachers must discern whether or not to address such an offense. I believe one must, but finding the way to do so is extremely challenging.
We could read both 17:5-6 and 17:7-10 as rebukes of the apostles. They ask for more faith, just as we do. In reply, Jesus scolds them for lacking even mustard seed faith and suggests they should not expect reward or praise for their service. Perhaps, however, there is more to the story. When Jesus’ followers ask for faith, what do we want? Some might desire that faith brings a certain kind of certainty, perhaps even superiority. Faith, then, becomes an accomplishment. Some seek a mystical experience, a faith that works like a drug and helps us get through life’s ordinary challenges. Some aspire to faith as an antidote to struggle. With enough faith, the televangelists tell us, we can conquer doubt, illness, even economic hardship.
In this light, mustard seed faith and modest discipleship may be just what we need. By God’s grace, discipleship requires not unshakable confidence or spectacular accomplishments. Luke’s Jesus indeed makes extraordinary demands of his disciples, yet sometimes discipleship requires ordinary and daily practices of fidelity and service.
May I digress for a word of personal testimony? Though raised in the church-centered Bible Belt, I did not grow up in church. When I was twelve, I spent a week in the hospital with a hip injury. I received two visits, one from my aunt and uncle’s part-time pastor and one from a church youth group. (The youth group brought a cutely packaged soap and washcloth.) Just a few years later, when I could embrace my faith, I remembered both of those visits. That’s the kind of thing Christians do.
Unfortunately, our culture has acquired a taste for spectacular spirituality. By the grace of God, mustard seed faith and ordinary discipleship more often suffice.