After dealing with the great issues of repentance and forgiveness, Luke tells us that the repentant ones should be trained in faith in order to grow spiritually. Luke 17:5 says,

⁵ And the apostles said to the Lord, “Increase our faith!”

 Luke had not called them apostles since Luke 9:10 when the seventy were sent out. It suggests that to move from discipleship to apostleship requires a new level of faith. The Greek word translated “increase” is prostithemi, a compound word made up of pros, “toward, or a face-to-face confrontation” and tithemi, “to add, or establish.” The word prostithemi denotes moving toward a face-to-face encounter with whatever God has set up or established.

The apostles desired such an encounter in order to move from discipleship to apostleship. Jesus answered them in Luke 17:6,

⁶ And the Lord said, “If you had faith like a mustard seed, you would say to this mulberry tree, ‘Be uprooted and be planted in the sea’; and it would obey you.”

A mustard seed was a very tiny seed, but it was all that was needed to rearrange one’s environment. On another occasion, when the disciples were unable to deliver a boy from a demon, they asked Jesus why they had failed. Matt. 17:20 says,

²⁰ And He said to them, “Because of the littleness of your faith; for truly I say to you, if you have faith as a mustard seed, you shall say to this mountain, ‘Move from here to there,’ and it shall move; and nothing shall be impossible to you.”

On that occasion, a nearby hill or mountain served as the point of illustration, whereas in Luke 17:6 they were near a mulberry tree. Later, in Matt. 21:21 Jesus made a similar statement near Jerusalem,

²¹ And Jesus answered and said to them, “Truly I say to you, if you have faith, and do not doubt, you shall not only do what was done to the fig tree, but even if you say to this mountain, ‘Be taken up and cast into the sea,’ it shall happen.”

Jesus did not intend for them to transplant mulberry trees or to cast literal mountains into the sea. He used figurative language to speak of obstacles or opposition. The “mountain,” in this case was equated to the fig tree, which Jesus had cursed to become perpetually fruitless. Both the fig tree and the mountain represented the nation of Judea itself. Jesus figuratively cast it into the sea in His first appearance, but taught His disciples to do the same at the end of the age. Fruitless trees take up space that could otherwise be used for fruit-bearing trees, and hence these represent opposition to the true “mountain of God.”

Humbly Serve God First

Luke 17:7-10 continues with a more specific answer about adding to one’s faith,

⁷ But which of you, having a slave plowing or tending sheep, will say to him when he has come in from the field, “Come immediately and sit down to eat”? ⁸ But will he not say to him, “Prepare something for me to eat, and properly clothe yourself and serve me until I have eaten and drunk; and afterward you will eat and drink”?

Keep in mind that Jesus’ statement answered the apostles’ question about adding to their faith. Jesus told them that they were to prepare themselves by serving God with humility and to understand that God’s needs and desires took priority over their own needs. This is a reference to the fact that prior to full maturity, we are God’s slaves, training to become His sons (Gal. 4:1-3). Likewise, discipleship training is learning to be a good servant before one is ready to be an apostle.

⁹ “He does not thank the slave because he did the things which were commanded, does he? ¹⁰ So you too, when you do all the things which are commanded you, say, ‘We are unworthy slaves; we have done only that which we ought to have done’.”

Living according to God’s commandments is the basic minimum requirement. This includes not only the general way of life taught in the law itself, but also hearing God’s voice and learning to obey the leading of the Spirit in specific matters. These are things learned in discipleship training. Many are proud of their achievements in discipleship training, but Jesus said that such disciples are still relatively useless (“unprofitable,” KJV) and have not yet even turned a profit for their Master!

Rather than being discouraged by this statement, the disciples knew that when their training was completed, they would be sent out as very useful apostles. Their face-to-face confrontation with Christ would establish their faith and add to it continually in the days ahead. Their faith was yet the size of a mustard seed, but it was the basic minimum requirement needed for discipleship. Soon their faith as servants of God would sprout and bear fruit, making them extremely fruitful and profitable to the Kingdom.

The Ten Lepers

Leprosy was a biblical type of mortality. It was a slow death. In Lev. 13:45 lepers were commanded to identify themselves to passersby by shouting, “Unclean! Unclean!” But in the next chapter we are given the law of the cleansing of lepers, which teaches us the lawful path to immortality. This law presumes that God has healed the leper, for only then would he go to the priest for confirmation of such healing, so that he could be pronounced clean.

Luke 17:11-14 says,

¹¹ And it came about while He was on the way to Jerusalem, that He was passing between Samaria and Galilee. ¹² And as He entered a certain village, ten leprous men who stood at a distance met Him; ¹³ and they raised their voices, saying, “Jesus, Master, have mercy on us!” ¹⁴ And when He saw them, He said to them, “Go and show yourselves to the priests.” And it came about that as they were going, they were cleansed.

This incident took place near the border of Samaria and Galilee. Jews usually bypassed Samaria, if at all possible, by travelling on the road across the Jordan. They walked south and then crossed the Jordan near the city of Jericho, and then walked up the mountain to Jerusalem. We see here that Jesus was “on the way to Jerusalem,” and we know from Luke 18:35 that He later passed through Jericho. Therefore, it is most likely that Jesus met these lepers on the Decapolis road on the east side of the Jordan River which marked the border with Samaria.

The Jews and Samaritans did not get along with each other. But we find from Luke 17:16 that one of the ten lepers was a Samaritan. The others, presumably, were Jews. Being lepers had united them, for none of the Jewish lepers could say of the Samaritan, “you are unclean; stay away from me.” They all had leprosy in common.

So it is also with mortality, which is common to all men. Mortality makes all men unclean in the ultimate sense. While the Mosaic law gave instructions about how to be cleansed from various forms of uncleanness, no ritual could cleanse a man from touching his own dead, mortal body. It takes an act of God to cleanse mortals.

No doubt, as Jesus and the disciples walked toward the band of lepers, they shouted their usual, “Unclean! Unclean!” as commanded in the law. Luke does not tell us how they came to recognize Jesus, but when they did, they immediately begged for mercy. They had heard of Jesus’ miracles of healing and perhaps could do nothing about it until Jesus came to them. So the Spirit led Jesus through Samaria, instead of avoiding that country.

Jesus did not touch the lepers, as He had done earlier in Matt. 8:3. He simply told them to assume they had been healed and to go by faith to the priest for inspection. Herein is the great lesson of faith presented in Luke’s account. It is about faith that reckons a matter to be accomplished even before it is seen.

The idea of reckoning is presented more fully in Romans 4, where the word logizomai is translated in the KJV as “reckoned,” “counted,” and “imputed.” The definition of this word is found in Rom. 4:17 (KJV), where God “calleth those things which be not as though they were.” The Emphatic Diaglott renders it, “calls things not in being, as though existing.”

Paul uses Abraham to illustrate such faith. God promised to make Abraham a father of many nations. Abraham had no children at all, making him a father of no nations at all. But “Abraham believed God, and it was reckoned [logizomai] to him as righteousness” (Rom. 4:3). The lesson for us is that by faith we too receive righteousness. Rom. 4:23, 24 says,

²³ Now not for his sake only was it written, that it was reckoned to him, ²⁴ but for our sake also, to whom it will be reckoned, as those who believe in Him who raised Jesus our Lord from the dead.

Such faith, which is able to believe God’s promise and reckon it done even before it is seen, is what we see with the ten lepers. When they began their long journey toward Jerusalem to be inspected by the priest, they had not yet seen their healing. Yet they believed Jesus, as Paul said in Rom. 4:21,

²¹ and being fully assured that what He had promised, He was able also to perform.

As Paul’s companion, Luke was well grounded in Abrahamic faith and understood the significance of Jesus’ reason for telling the ten lepers to go to the priest before they could see that they had been healed. The ten lepers, in fact, became instructors to Jesus’ own disciples, answering their request for additional faith.

It would appear from this that the ability to reckon represents an increase in faith to go beyond the size of the mustard seed. Faith is not wishful thinking, but a knowing that it is an accomplished fact ahead of time. It is not hope, but expectation.

Thankfulness

Luke 17:15-19 concludes the story, showing that thankfulness comes by knowing and is thus the capstone of faith:

¹⁵ Now one of them, when he saw that he had been healed, turned back, glorifying God with a loud voice, ¹⁶ and he fell on his face at His feet, giving thanks to Him. And he was a Samaritan. ¹⁷ And Jesus answered and said, “Were there not ten cleansed? But the nine—where are they? ¹⁸ Was no one found who turned back to give glory to God, except this foreigner?” ¹⁹ And He said to him, “Rise, and go your way; your faith has made you well.”

Luke makes a point of telling us that Samaritans, along with Jews, could have faith and come into immortality. Just as the whole world is equally condemned by sin and death (spiritual “leprosy”), whether Jew, Greek, or Samaritan, so also does Jesus provide the common solution that all mankind needs.

Not only did Jesus heal the Samaritan leper, but he also had faith equal to or greater than his Jewish friends. Luke implies, with a note of irony, that the Samaritan was more thankful, perhaps because he knew that any other rabbi, possessing the power to heal lepers, would have healed just nine of them.

By writing about Samaritans in a positive light, Dr. Luke not only teaches us about faith and thankfulness, but also heals the gaping wound between Jews and Samaritans and heals the perceived breach between God and the Samaritans.