diff --git a/server/routes/bible-passage.js b/server/routes/bible-passage.js
index 745d873..5a4d592 100644
--- a/server/routes/bible-passage.js
+++ b/server/routes/bible-passage.js
@@ -1,21 +1,19 @@
+import { BIBLE_BOOKS } from '../../shared/bible-books.js'
+
 const passageCache = new Map()
 
-const BOLLS_BOOK_MAP = {
-  genesis: 1, exodus: 2, leviticus: 3, numbers: 4, deuteronomy: 5,
-  joshua: 6, judges: 7, ruth: 8, '1samuel': 9, '2samuel': 10,
-  '1kings': 11, '2kings': 12, '1chronicles': 13, '2chronicles': 14,
-  ezra: 15, nehemiah: 16, esther: 17, job: 18, psalms: 19, proverbs: 20,
-  ecclesiastes: 21, songofsolomon: 22, isaiah: 23, jeremiah: 24,
-  lamentations: 25, ezekiel: 26, daniel: 27, hosea: 28, joel: 29,
-  amos: 30, obadiah: 31, jonah: 32, micah: 33, nahum: 34, habakkuk: 35,
-  zephaniah: 36, haggai: 37, zechariah: 38, malachi: 39,
-  matthew: 40, mark: 41, luke: 42, john: 43, acts: 44,
-  romans: 45, '1corinthians': 46, '2corinthians': 47, galatians: 48,
-  ephesians: 49, philippians: 50, colossians: 51, '1thessalonians': 52,
-  '2thessalonians': 53, '1timothy': 54, '2timothy': 55, titus: 56,
-  philemon: 57, hebrews: 58, james: 59, '1peter': 60, '2peter': 61,
-  '1john': 62, '2john': 63, '3john': 64, jude: 65, revelation: 66,
-}
+// Keyed by lowercase, whitespace-stripped book name/alias (matching the format
+// the admin's "Bible Book" field and the /api/bible-passage `book` query param
+// both use), mapped to bolls.life's numeric book id (canonical order, 1-66).
+// Derived from the shared BIBLE_BOOKS list so it can't drift from the client's
+// Scripture Index book map (src/App.tsx's SI_BOOK_MAP).
+const BOLLS_BOOK_MAP = {}
+BIBLE_BOOKS.forEach((b, index) => {
+  const bookNum = index + 1
+  for (const key of [b.name.toLowerCase(), ...(b.aliases ?? [])]) {
+    BOLLS_BOOK_MAP[key.replace(/\s+/g, '')] = bookNum
+  }
+})
 
 function parseReference(reference) {
   const stripped = reference.replace(/^[a-z]+/i, '')
diff --git a/shared/bible-books.js b/shared/bible-books.js
new file mode 100644
index 0000000..052d9fc
--- /dev/null
+++ b/shared/bible-books.js
@@ -0,0 +1,87 @@
+// Canonical Protestant Bible book list, in canonical (Genesis → Revelation) order.
+//
+// This is the single source of truth for book names/aliases, shared between the
+// client (src/App.tsx, for the Scripture Index page) and the server
+// (server/routes/bible-passage.js, for the BSB/bolls.life passage-fetch API).
+// Previously these lived as three independent, hand-maintained lists with
+// different key formats (spaced names + 3-letter ids in the client, unspaced
+// names + numeric ids on the server) that could silently drift out of sync.
+//
+// - `id` is the 3-letter USFM-style book id used by the bible.helloao.org API.
+// - bolls.life's book numbering is exactly this array's 1-based canonical order,
+//   so no separate numeric-id table is needed — see bookNumberFor() below.
+// - `aliases` are additional short forms admins/users might type (abbreviations).
+export const BIBLE_BOOKS = [
+  { id: 'GEN', name: 'Genesis', aliases: ['gen'] },
+  { id: 'EXO', name: 'Exodus', aliases: ['exo'] },
+  { id: 'LEV', name: 'Leviticus', aliases: ['lev'] },
+  { id: 'NUM', name: 'Numbers', aliases: ['num'] },
+  { id: 'DEU', name: 'Deuteronomy', aliases: ['deut'] },
+  { id: 'JOS', name: 'Joshua', aliases: ['josh'] },
+  { id: 'JDG', name: 'Judges', aliases: ['judg'] },
+  { id: 'RUT', name: 'Ruth' },
+  { id: 'SA1', name: '1 Samuel', aliases: ['1 sam'] },
+  { id: 'SA2', name: '2 Samuel', aliases: ['2 sam'] },
+  { id: 'KI1', name: '1 Kings', aliases: ['1 kgs'] },
+  { id: 'KI2', name: '2 Kings', aliases: ['2 kgs'] },
+  { id: 'CH1', name: '1 Chronicles', aliases: ['1 chr'] },
+  { id: 'CH2', name: '2 Chronicles', aliases: ['2 chr'] },
+  { id: 'EZR', name: 'Ezra' },
+  { id: 'NEH', name: 'Nehemiah', aliases: ['neh'] },
+  { id: 'EST', name: 'Esther', aliases: ['esth'] },
+  { id: 'JOB', name: 'Job' },
+  { id: 'PSA', name: 'Psalms', aliases: ['ps', 'psa', 'psalm'] },
+  { id: 'PRO', name: 'Proverbs', aliases: ['prov'] },
+  { id: 'ECC', name: 'Ecclesiastes', aliases: ['eccl'] },
+  { id: 'SNG', name: 'Song of Solomon', aliases: ['song'] },
+  { id: 'ISA', name: 'Isaiah', aliases: ['isa'] },
+  { id: 'JER', name: 'Jeremiah', aliases: ['jer'] },
+  { id: 'LAM', name: 'Lamentations', aliases: ['lam'] },
+  { id: 'EZK', name: 'Ezekiel', aliases: ['ezek'] },
+  { id: 'DAN', name: 'Daniel', aliases: ['dan'] },
+  { id: 'HOS', name: 'Hosea', aliases: ['hos'] },
+  { id: 'JOL', name: 'Joel' },
+  { id: 'AMO', name: 'Amos' },
+  { id: 'OBA', name: 'Obadiah', aliases: ['obad'] },
+  { id: 'JNA', name: 'Jonah' },
+  { id: 'MIC', name: 'Micah', aliases: ['mic'] },
+  { id: 'NAH', name: 'Nahum', aliases: ['nah'] },
+  { id: 'HAB', name: 'Habakkuk', aliases: ['hab'] },
+  { id: 'ZEP', name: 'Zephaniah', aliases: ['zeph'] },
+  { id: 'HAG', name: 'Haggai', aliases: ['hag'] },
+  { id: 'ZEC', name: 'Zechariah', aliases: ['zech'] },
+  { id: 'MAL', name: 'Malachi', aliases: ['mal'] },
+  { id: 'MAT', name: 'Matthew', aliases: ['matt'] },
+  { id: 'MRK', name: 'Mark' },
+  { id: 'LUK', name: 'Luke' },
+  { id: 'JHN', name: 'John' },
+  { id: 'ACT', name: 'Acts' },
+  { id: 'ROM', name: 'Romans', aliases: ['rom'] },
+  { id: 'CO1', name: '1 Corinthians', aliases: ['1 cor'] },
+  { id: 'CO2', name: '2 Corinthians', aliases: ['2 cor'] },
+  { id: 'GAL', name: 'Galatians', aliases: ['gal'] },
+  { id: 'EPH', name: 'Ephesians', aliases: ['eph'] },
+  { id: 'PHP', name: 'Philippians', aliases: ['phil'] },
+  { id: 'COL', name: 'Colossians', aliases: ['col'] },
+  { id: 'TH1', name: '1 Thessalonians', aliases: ['1 thess'] },
+  { id: 'TH2', name: '2 Thessalonians', aliases: ['2 thess'] },
+  { id: 'TI1', name: '1 Timothy', aliases: ['1 tim'] },
+  { id: 'TI2', name: '2 Timothy', aliases: ['2 tim'] },
+  { id: 'TIT', name: 'Titus' },
+  { id: 'PHM', name: 'Philemon', aliases: ['philem'] },
+  { id: 'HEB', name: 'Hebrews', aliases: ['heb'] },
+  { id: 'JAM', name: 'James', aliases: ['jas'] },
+  { id: 'PE1', name: '1 Peter', aliases: ['1 pet'] },
+  { id: 'PE2', name: '2 Peter', aliases: ['2 pet'] },
+  { id: 'JO1', name: '1 John' },
+  { id: 'JO2', name: '2 John' },
+  { id: 'JO3', name: '3 John' },
+  { id: 'JDE', name: 'Jude', aliases: ['jude'] },
+  { id: 'REV', name: 'Revelation', aliases: ['rev'] },
+]
+
+/** bolls.life's numeric book id: just this list's 1-based canonical position. */
+export function bookNumberFor(usfmId) {
+  const index = BIBLE_BOOKS.findIndex(b => b.id === usfmId)
+  return index === -1 ? null : index + 1
+}
diff --git a/src/App.tsx b/src/App.tsx
index 090027d..83d142f 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -12,6 +12,7 @@ import { usePageMeta } from './hooks/usePageMeta'
 import { useGlobalSearch } from './hooks/useGlobalSearch'
 import { GlobalSearch } from './components/GlobalSearch'
 import { EpisodeAudioPlayer } from './components/EpisodeAudioPlayer'
+import { BIBLE_BOOKS } from '../shared/bible-books.js'
 import './App.css'
 import { sendEvent, useScrollDepthTracking, useTimeOnPage, useUTMCapture, useLinkClickTracking } from './analytics'
 
@@ -1983,75 +1984,9 @@ function ResourcesPage({ content }: { content: SiteContent }) {
   )
 }
 
-const BIBLE_BOOKS: Array<{ id: string; name: string; aliases?: string[] }> = [
-  { id: 'GEN', name: 'Genesis', aliases: ['gen'] },
-  { id: 'EXO', name: 'Exodus', aliases: ['exo'] },
-  { id: 'LEV', name: 'Leviticus', aliases: ['lev'] },
-  { id: 'NUM', name: 'Numbers', aliases: ['num'] },
-  { id: 'DEU', name: 'Deuteronomy', aliases: ['deut'] },
-  { id: 'JOS', name: 'Joshua', aliases: ['josh'] },
-  { id: 'JDG', name: 'Judges', aliases: ['judg'] },
-  { id: 'RUT', name: 'Ruth' },
-  { id: 'SA1', name: '1 Samuel', aliases: ['1 sam'] },
-  { id: 'SA2', name: '2 Samuel', aliases: ['2 sam'] },
-  { id: 'KI1', name: '1 Kings', aliases: ['1 kgs'] },
-  { id: 'KI2', name: '2 Kings', aliases: ['2 kgs'] },
-  { id: 'CH1', name: '1 Chronicles', aliases: ['1 chr'] },
-  { id: 'CH2', name: '2 Chronicles', aliases: ['2 chr'] },
-  { id: 'EZR', name: 'Ezra' },
-  { id: 'NEH', name: 'Nehemiah', aliases: ['neh'] },
-  { id: 'EST', name: 'Esther', aliases: ['esth'] },
-  { id: 'JOB', name: 'Job' },
-  { id: 'PSA', name: 'Psalms', aliases: ['ps', 'psa', 'psalm'] },
-  { id: 'PRO', name: 'Proverbs', aliases: ['prov'] },
-  { id: 'ECC', name: 'Ecclesiastes', aliases: ['eccl'] },
-  { id: 'SNG', name: 'Song of Solomon', aliases: ['song'] },
-  { id: 'ISA', name: 'Isaiah', aliases: ['isa'] },
-  { id: 'JER', name: 'Jeremiah', aliases: ['jer'] },
-  { id: 'LAM', name: 'Lamentations', aliases: ['lam'] },
-  { id: 'EZK', name: 'Ezekiel', aliases: ['ezek'] },
-  { id: 'DAN', name: 'Daniel', aliases: ['dan'] },
-  { id: 'HOS', name: 'Hosea', aliases: ['hos'] },
-  { id: 'JOL', name: 'Joel' },
-  { id: 'AMO', name: 'Amos' },
-  { id: 'OBA', name: 'Obadiah', aliases: ['obad'] },
-  { id: 'JNA', name: 'Jonah' },
-  { id: 'MIC', name: 'Micah', aliases: ['mic'] },
-  { id: 'NAH', name: 'Nahum', aliases: ['nah'] },
-  { id: 'HAB', name: 'Habakkuk', aliases: ['hab'] },
-  { id: 'ZEP', name: 'Zephaniah', aliases: ['zeph'] },
-  { id: 'HAG', name: 'Haggai', aliases: ['hag'] },
-  { id: 'ZEC', name: 'Zechariah', aliases: ['zech'] },
-  { id: 'MAL', name: 'Malachi', aliases: ['mal'] },
-  { id: 'MAT', name: 'Matthew', aliases: ['matt'] },
-  { id: 'MRK', name: 'Mark' },
-  { id: 'LUK', name: 'Luke' },
-  { id: 'JHN', name: 'John' },
-  { id: 'ACT', name: 'Acts' },
-  { id: 'ROM', name: 'Romans', aliases: ['rom'] },
-  { id: 'CO1', name: '1 Corinthians', aliases: ['1 cor'] },
-  { id: 'CO2', name: '2 Corinthians', aliases: ['2 cor'] },
-  { id: 'GAL', name: 'Galatians', aliases: ['gal'] },
-  { id: 'EPH', name: 'Ephesians', aliases: ['eph'] },
-  { id: 'PHP', name: 'Philippians', aliases: ['phil'] },
-  { id: 'COL', name: 'Colossians', aliases: ['col'] },
-  { id: 'TH1', name: '1 Thessalonians', aliases: ['1 thess'] },
-  { id: 'TH2', name: '2 Thessalonians', aliases: ['2 thess'] },
-  { id: 'TI1', name: '1 Timothy', aliases: ['1 tim'] },
-  { id: 'TI2', name: '2 Timothy', aliases: ['2 tim'] },
-  { id: 'TIT', name: 'Titus' },
-  { id: 'PHM', name: 'Philemon', aliases: ['philem'] },
-  { id: 'HEB', name: 'Hebrews', aliases: ['heb'] },
-  { id: 'JAM', name: 'James', aliases: ['jas'] },
-  { id: 'PE1', name: '1 Peter', aliases: ['1 pet'] },
-  { id: 'PE2', name: '2 Peter', aliases: ['2 pet'] },
-  { id: 'JO1', name: '1 John' },
-  { id: 'JO2', name: '2 John' },
-  { id: 'JO3', name: '3 John' },
-  { id: 'JDE', name: 'Jude', aliases: ['jude'] },
-  { id: 'REV', name: 'Revelation', aliases: ['rev'] },
-]
-
+// Canonical book list lives in shared/bible-books.js so the client (Scripture
+// Index book matching, below) and the server (server/routes/bible-passage.js,
+// the BSB passage-fetch API) can't drift out of sync with each other.
 const SI_BOOK_MAP: Record<string, string> = {}
 const SI_BOOK_NAME: Record<string, string> = {}
 const SI_BOOK_ORDER: string[] = []
diff --git a/tsconfig.app.json b/tsconfig.app.json
index af516fc..33bf506 100644
--- a/tsconfig.app.json
+++ b/tsconfig.app.json
@@ -7,6 +7,7 @@
     "module": "ESNext",
     "types": ["vite/client"],
     "skipLibCheck": true,
+    "allowJs": true,
 
     /* Bundler mode */
     "moduleResolution": "bundler",
@@ -24,5 +25,5 @@
     "noFallthroughCasesInSwitch": true,
     "noUncheckedSideEffectImports": true
   },
-  "include": ["src"]
+  "include": ["src", "shared"]
 }