Matthew Chapter 18 — The Cost of Discipleship and the Salt Saying

🔗Overview

UPDV chapter 18 covers the cost of discipleship (18:1-3), the tower builder and king at war parables (18:4-9), and the salt saying (18:10). This material comes from canonical Matt 10:37-38, Matt 5:13, and Luke 14:25-35.

The chapter continues directly from where chapter 17 ended. Chapter 17 closed with the great banquet parable (Luke 14:15-24); chapter 18 picks up at Luke 14:25 and follows Luke's order through 14:35. The compiler scattered this material across three different contexts — the Sermon on the Mount (Matt 5:13), the mission discourse (Matt 10:37-38), and omission of the tower builder and king at war entirely. The UPDV reassembles the shared sayings source discipleship block and restores the L material that Luke placed between the family-and-cross sayings and the salt conclusion.

This chapter also makes visible a methodological reality that previous chapters handled implicitly: the UPDV is not a pure shared-source extraction but a Lukan-baseline reconstruction. It defaults to Luke's architectural framework — including his narrative frames (18:1), his editorial bridges (18:9), and his source fusions (18:10a) — to hold the shared Matthew/Luke sayings material together as a readable text. The alternative would be a fragmentary collection of isolated sayings, which is what the shared sayings source actually was. The UPDV chose continuity over purity, and this chapter is where that choice becomes most transparent.

The chapter is short — only ten verses — but it raises a significant shared-source reconstruction question. Luke 14:26 has μισέω (miseō, "hate"): "If any man comes to me, and does not hate his own father..." Matthew 10:37 has φιλέω ὑπέρ (phileō huper, "love more than"): "He who loves father or mother more than me..." The scholarly consensus is that the shared sayings source had "hate" and the compiler softened it. The UPDV keeps the compiler's softer form but adopts Luke's refrain ("can't be my disciple" instead of "is not worthy of me"), producing a hybrid that splits the difference between the two traditions.

🔗The Cost of Discipleship: Family and Cross (18:1-3)

"Now there went with him great multitudes: and he turned, and said to them." The narrative frame (18:1) comes from Luke 14:25. The family saying (18:2) is sourced from the compiler's Matt 10:37, and the cross saying (18:3) from Matt 10:38. Both are shared Matthew/Luke sayings material paralleled at Luke 14:26-27.

The UPDV's handling of 18:2 is a partial revision. The compiler's Matt 10:37 reads: "He who loves father or mother more than me is not worthy of me; and he who loves son or daughter more than me is not worthy of me." The UPDV replaces the consequence formula with Luke's: "can't be my disciple." Davies and Allison are explicit that the change from μαθητής (mathētēs, "disciple") to ἄξιος (axios, "worthy") was the compiler's work, not a translation variant: "Pace Manson, Teaching, pp. 237-8, there is no need to regard 'he is not worthy of me' and 'he is not able to be my disciple' as translation variants." They note that ἄξιος "appears seven times in chapter 10" — part of the compiler's thematic vocabulary for his mission discourse. Luke's "can't be my disciple" preserves the shared source's teacher-disciple framework; the compiler reframed it around worthiness to suit his christological emphasis.

But the UPDV does not apply the same correction to 18:3. The cross saying retains the compiler's wording verbatim: "And he who does not take his cross and follow after me, is not worthy of me." Luke 14:27 has "can't be my disciple" here too, using the same refrain three times (14:26, 27, 33) to create a structural unity. The UPDV corrects the refrain in 18:2 but leaves it uncorrected in 18:3, producing a sequence where consecutive verses use different consequence formulas for the same conditional structure. This is an inconsistency that a future revision should resolve — if "can't be my disciple" is shared-source original for 18:2, it is equally shared-source original for 18:3.

The deeper question is whether the UPDV should have used Luke's "hate" (μισέω) instead of the compiler's "loves more than" (φιλέω ὑπέρ). Davies and Allison are unambiguous: "[the shared source's] very Semitic 'does not hate' has been altered to the less offensive but still accurate 'love more.'" They add that "Matthew never uses 'hate' in a positive sense" — the change was driven by the compiler's stylistic preferences, not by a different source tradition. Marshall confirms: "Matthew's form has toned down the force of the original (Lucan) saying." He notes the Semitic background of μισέω — not psychological hatred but renunciation, as in Genesis 29:31 (Leah "hated" means "loved less") and Deuteronomy 21:15-17 (the "hated" wife's inheritance rights). Nolland pushes back against reducing "hate" to "love less": "it is probably not right, as is often said, that the Semitic idiom actually means 'love less than.'" He links the language to Deuteronomy 33:9, where the Levites demonstrate loyalty to God by disregarding family ties — "single-mindedness that disregarded their own family ties."

The UPDV's defense for keeping "loves more than me" is that the source chart maps 18:2 to Matt 10:37, meaning the UPDV starts from the compiler's text and revises toward the shared sayings source rather than replacing wholesale with Luke. It preserves the compiler's family list — "father or mother... son or daughter" (two pairs) — rather than Luke's expanded list of seven ("father, mother, wife, children, brothers, sisters, yes, and even his own life"). This is actually a sound shared-source decision: most scholars think Luke expanded the list. Nolland notes Luke "will be responsible for some expansion of the range of family specified." Marshall sees influence from Luke 18:29 and Mark 10:29 in the additions. The UPDV keeps what is likely closer to the shared source's shorter family catalog while correcting the consequence formula.

But the retention of "loves more than me" over "hate" remains a tension in the UPDV's method. The project's stated goal is to strip the compiler's editorial changes and recover the shared sayings source. Here the compiler's change is identified with high confidence — D&A, Marshall, Bovon, and Nolland all agree that the shared sayings source had μισέω and the compiler softened it — yet the UPDV keeps the softened form. The practical reason is readability: "hate" in English carries connotations that the Semitic original does not, and explaining the idiom requires a footnote that the text format may not support. But the scholarly reason points toward revision: if the shared sayings source had "hate," a shared-source reconstruction should print "hate" and let the commentary explain the Semitic background. This is a case, like the salt ending and the 18:3 consequence formula, where the UPDV preserves compiler redaction that its own source analysis identifies as secondary.

The cross saying (18:3) comes from the shared-source version at Matt 10:38 rather than the Markan version at Matt 16:24 (= Mark 8:34). Davies and Allison identify both as independent traditions: "The saying about the cross appears five times in the synoptics: Mt 10:38; 16:24; Mk 8:34; Lk 9:23; 14:27. Mt 16:24 and Lk 9:23 derive from Mk 8:34; Mt 10:38 and Lk 14:27 are from [the shared sayings source]." They judge the Markan version — "If any man would come after me, let him deny himself and take up his cross and follow me" — as "more primitive" than the shared sayings source negation form. The UPDV retains the shared source's negation form, which fits the discipleship-conditions structure of Luke 14:26-27.

🔗Counting the Cost: Tower Builder and King at War (18:4-9)

"For which of you⁺, desiring to build a tower, does not first sit down and count the cost, whether he has the means to complete it?" The tower builder (18:4-6) and king at war (18:7-8) parables come from Luke 14:28-32. The renunciation saying (18:9) comes from Luke 14:33.

These are Luke-only material. Bovon assigns them explicitly: "The two parables are true parables, of a type characteristic of L." Davies and Allison confirm this implicitly: their shared-source reconstruction table lists Luke 14:26-27 (= Matt 10:37-38) and Luke 14:34-35 (= Matt 5:13) as the shared sayings source, but Luke 14:28-33 is entirely absent. In the shared sayings source, the salt saying followed directly after the family-and-cross conditions with no intervening parables.

The reader should recognize that the UPDV is not reconstructing the shared source's sequence here. D&A's evidence shows the shared sayings source had the family/cross sayings immediately followed by the salt saying — a tight discipleship block with no parables in between. The UPDV breaks this known shared-source sequence by inserting six verses of L material between them. This is not a case of filling a "structural gap" where shared Matthew/Luke sayings material has been lost; it is a deliberate choice to follow Luke's fuller narrative arrangement over the bare shared-source text. The UPDV's operating principle throughout these chapters has been to use Luke's order as the baseline, including the L material that Luke wove between shared-source blocks. The cost of this principle is that it sometimes overwrites shared-source sequence it claims to reconstruct. The benefit is a continuous, readable text rather than a collection of isolated sayings — but the reader should understand that what stands between 18:3 and 18:10 is Luke's editorial expansion, not the shared sayings source.

Nolland observes that the two parables "have been formulated together" and "probably go back to the historical Jesus." He raises an intriguing possibility about their original meaning: Hunzinger proposed that they "pointed not to human deliberation but to God's reliability — if even humans plan carefully before undertaking great enterprises, how much more does God. He will complete what he has begun with Jesus' ministry." On this reading, the parables were originally about divine faithfulness, not human calculation, and Luke recontextualized them as discipleship warnings. Nolland finds the proposal attractive but uncertain.

Bovon notes a structural parallel in Gospel of Thomas 98, where an assassin tests his sword on a wall before killing his victim — "the same parabolic pattern: an action requiring preparation." The existence of three such parables (tower, war, assassin) suggests a widespread tradition of "count the cost" teaching, even if only Luke preserved the first two.

The renunciation saying (18:9) — "So therefore whoever he is of you⁺ who does not renounce all that he has, he can't be my disciple" — is identified by both Nolland and Bovon as Lukan composition, not traditional material. Nolland calls it "a Lukan formulation, inspired by 12:33 and 18:22." It serves as Luke's editorial bridge, linking the L parables back to the shared sayings source discipleship theme of 14:26-27 by repeating the "can't be my disciple" refrain a third time. The UPDV includes it as part of the L block, consistent with the structural gap principle applied throughout these chapters.

🔗The Salt Saying (18:10)

"Salt therefore is good: but if the salt has lost its savor, how will it be salted?" The salt saying (18:10) comes from canonical Matt 5:13, which is shared Matthew/Luke sayings material with a Markan parallel at Mark 9:50 and a Lukan parallel at Luke 14:34-35.

The UPDV's reconstruction is a hybrid. The opening — "Salt therefore is good" (Καλόν οὖν τό ἅλας, Kalon oun to halas) — follows Luke's form rather than the compiler's "You are the salt of the earth" (Ὑμεῖς ἐστε τό ἅλας τῆς γῆς). Davies and Allison identify the compiler's address formula as "redactional": "You are the salt of the earth" is his own creation, introducing a shared Matthew/Luke saying with a pedagogical frame. Bovon, however, assigns Luke's "Salt is good" not to the shared sayings source but to Mark (Mark 9:50a, Καλόν τό ἅλας). Luke fused his two sources — Mark's opening with the shared source's substance — and the UPDV follows Luke's fused form rather than reconstructing the pure shared-source form.

The question verb — "how will it be salted?" (ἁλισθήσεται) — follows the compiler's form rather than Luke's "how will it be seasoned?" (ἀρτυθήσεται). Nolland notes that Luke's ἀρτυθήσεται likely comes from Mark (ἀρτύσετε in Mark 9:50), so the compiler's ἁλισθήσεται may actually be closer to the shared sayings source.

The ending is where the UPDV makes its most consequential choice. Luke's shared-source form reads: "It is fit neither for the land nor for the dunghill: men cast it out." The compiler has: "It is from then on good for nothing, but to be cast out and trodden under foot of men." Davies and Allison judge Luke's form more original: "Luke seems more original... εἰς οὐδὲν ἰσχύει summarizes Luke's 'it is fit neither for the land nor for the dunghill.'" In other words, the compiler condensed the shared source's two-part verdict ("neither for the land nor for the dunghill") into a summary ("good for nothing"), then added his own embellishment ("trodden under foot of men"). The UPDV follows the compiler's embellished ending rather than Luke's more original shared-source form — an editorial inconsistency given that the opening of this same verse was corrected from Matthew toward Luke. If the UPDV replaces "You are the salt of the earth" with "Salt therefore is good" on shared-source reconstruction grounds, the same logic requires replacing "trodden under foot of men" with "neither for the land nor for the dunghill." A future revision should adopt Luke's ending, which D&A judge closer to the shared sayings source.

Marshall provides the key to the underlying Semitic wordplay. The verb μωρανθῇ (mōranthē, "become foolish/tasteless") — shared by both Matthew and Luke against Mark's ἄναλον γένηται — reflects the Hebrew root tpl, which means both "saltlessness" (tāpēl, Job 6:6) and "folly" (tiplāh, Jeremiah 23:13). The shared sayings source translator chose the "folly" meaning while Mark's source chose the "saltlessness" meaning — "two independent translations of the same Aramaic term." This shared μωρανθῇ is what proves the saying existed in the shared sayings source alongside Mark: "we must suppose that there was a [shared-source] wording in addition to the Markan wording."

On the shared sayings source placement: Davies and Allison's shared-source reconstruction table places the salt saying (item 36) immediately after the conditions of discipleship (item 35: Luke 14:26-27 = Matt 10:37-38). The compiler moved it from its shared-source position — after the family/cross sayings — to the Sermon on the Mount, where it serves as a thematic introduction. Luke preserves the shared source's order, placing the salt after the discipleship material. The UPDV follows Luke's shared-source sequence, which D&A confirm is original.

The UPDV drops Luke's concluding "He who has ears to hear, let him hear." Bovon assigns this to Markan influence (cf. Mark 9:50c, "Have salt in yourselves"), and it does not appear in shared-source form reconstructed from the Matthew/Luke agreement.

🔗What the UPDV Removes from This Section

Matt 5:13a ("You are the salt of the earth"): The compiler's redactional address formula, replaced by Luke's shared-source/Mark opening "Salt therefore is good." D&A: the address is Matthew's own creation.
Matt 10:37 — revised: "is not worthy of me" replaced by "can't be my disciple" (Luke 14:26's shared-source refrain). D&A: "[the shared source's] very Semitic 'does not hate' has been altered to the less offensive but still accurate 'love more'" — but the consequence formula ἄξιος is Matthean, not the shared sayings source.
Matt 10:39 ("He who finds his life will lose it; and he who loses his life for my sake will find it"): Omitted as a shared-source doublet. The same saying appears at Luke 17:33, where it is used in the UPDV's chapter 16 material. Bovon confirms that the shared sayings source had this saying elsewhere, not in the discipleship block: in the shared sayings source, sayings 1 (hate family) and 2 (bear cross) appeared together, but saying 3 (lose life) was placed later.

🔗References