diff --git a/ghost/package-json/lib/package-json.js b/ghost/package-json/lib/package-json.js
index 213a2a1521..b09aa11105 100644
--- a/ghost/package-json/lib/package-json.js
+++ b/ghost/package-json/lib/package-json.js
@@ -3,14 +3,17 @@ const Promise = require('bluebird');
 const fs = require('fs-extra');
 const join = require('path').join;
 const errors = require('@tryghost/errors');
+const tpl = require('@tryghost/tpl');
 
 const notAPackageRegex = /^\.|_messages|README.md|node_modules|bower_components/i;
 const packageJSONPath = 'package.json';
 
-/**
- * @typedef {Object} Ii18n
- * @prop {(key: string) => string} t
- */
+const messages = {
+    couldNotReadPackage: 'Could not read package.json file',
+    nameOrVersionMissing: '"name" or "version" is missing from theme package.json file.',
+    willBeRequired: 'This will be required in future. Please see {url}',
+    themeFileIsMalformed: 'Theme package.json file is malformed'
+};
 
 /**
  * # Package Utils
@@ -23,15 +26,6 @@ const packageJSONPath = 'package.json';
  *
  */
 module.exports = class PackageJson {
-    /**
-     * Creates an instance of PackageJson, an util used to read and validate package.json files
-     * @param {Object} dependencies
-     * @param {Ii18n} dependencies.i18n
-     */
-    constructor({i18n}) {
-        this.i18n = i18n;
-    }
-
     /**
      * ### Filter Packages
      * Normalizes packages read by read-packages so that the themes module can use them.
@@ -85,7 +79,7 @@ module.exports = class PackageJson {
             source = await fs.readFile(path);
         } catch (readError) {
             const err = new errors.IncorrectUsageError();
-            err.message = this.i18n.t('errors.utils.parsepackagejson.couldNotReadPackage');
+            err.message = tpl(messages.couldNotReadPackage);
             err.context = path;
             err.err = readError;
 
@@ -96,10 +90,10 @@ module.exports = class PackageJson {
             json = JSON.parse(source);
         } catch (parseError) {
             const err = new errors.IncorrectUsageError();
-            err.message = this.i18n.t('errors.utils.parsepackagejson.themeFileIsMalformed');
+            err.message = tpl(messages.themeFileIsMalformed);
             err.context = path;
             err.err = parseError;
-            err.help = this.i18n.t('errors.utils.parsepackagejson.willBeRequired', {url: 'https://ghost.org/docs/themes/'});
+            err.help = tpl(messages.willBeRequired, {url: 'https://ghost.org/docs/themes/'});
 
             return Promise.reject(err);
         }
@@ -108,9 +102,9 @@ module.exports = class PackageJson {
 
         if (!hasRequiredKeys) {
             const err = new errors.IncorrectUsageError();
-            err.message = this.i18n.t('errors.utils.parsepackagejson.nameOrVersionMissing');
+            err.message = tpl(messages.nameOrVersionMissing);
             err.context = path;
-            err.help = this.i18n.t('errors.utils.parsepackagejson.willBeRequired', {url: 'https://ghost.org/docs/themes/'});
+            err.help = tpl(messages.willBeRequired, {url: 'https://ghost.org/docs/themes/'});
 
             return Promise.reject(err);
         }
diff --git a/ghost/package-json/package.json b/ghost/package-json/package.json
index 2086b2e96f..de9e9354e7 100644
--- a/ghost/package-json/package.json
+++ b/ghost/package-json/package.json
@@ -27,6 +27,7 @@
   },
   "dependencies": {
     "@tryghost/errors": "^0.2.12",
+    "@tryghost/tpl": "^0.1.0",
     "bluebird": "^3.7.2",
     "fs-extra": "^10.0.0",
     "lodash": "^4.17.21"
diff --git a/ghost/package-json/test/filter.test.js b/ghost/package-json/test/filter.test.js
index 2ed3591d43..e86c558aa0 100644
--- a/ghost/package-json/test/filter.test.js
+++ b/ghost/package-json/test/filter.test.js
@@ -1,11 +1,7 @@
 require('./utils');
 const PackageJSON = require('../');
 
-const packageJSON = new PackageJSON({
-    i18n: {
-        t: key => key
-    }
-});
+const packageJSON = new PackageJSON();
 
 describe('lib/fs/package-json', function () {
     // @TODO: introduce some non-theme package examples
diff --git a/ghost/package-json/test/parse.test.js b/ghost/package-json/test/parse.test.js
index 1e156c9067..ccb3ee3fd5 100644
--- a/ghost/package-json/test/parse.test.js
+++ b/ghost/package-json/test/parse.test.js
@@ -4,11 +4,7 @@ const tmp = require('tmp');
 const fs = require('fs-extra');
 const PackageJSON = require('../');
 
-const packageJSON = new PackageJSON({
-    i18n: {
-        t: key => key
-    }
-});
+const packageJSON = new PackageJSON();
 
 describe('lib/fs/package-json: parse', function () {
     it('should parse valid package.json', function (done) {
@@ -52,9 +48,9 @@ describe('lib/fs/package-json: parse', function () {
                 done(new Error('packageJSON.parse succeeded, but should\'ve failed'));
             })
             .catch(function (err) {
-                err.message.should.equal('errors.utils.parsepackagejson.nameOrVersionMissing');
+                err.message.should.equal('"name" or "version" is missing from theme package.json file.');
                 err.context.should.equal(tmpFile.name);
-                err.help.should.equal('errors.utils.parsepackagejson.willBeRequired');
+                err.help.should.equal('This will be required in future. Please see https://ghost.org/docs/themes/');
 
                 done();
             })
@@ -78,9 +74,9 @@ describe('lib/fs/package-json: parse', function () {
                 done(new Error('packageJSON.parse succeeded, but should\'ve failed'));
             })
             .catch(function (err) {
-                err.message.should.equal('errors.utils.parsepackagejson.nameOrVersionMissing');
+                err.message.should.equal('"name" or "version" is missing from theme package.json file.');
                 err.context.should.equal(tmpFile.name);
-                err.help.should.equal('errors.utils.parsepackagejson.willBeRequired');
+                err.help.should.equal('This will be required in future. Please see https://ghost.org/docs/themes/');
 
                 done();
             })
@@ -102,9 +98,9 @@ describe('lib/fs/package-json: parse', function () {
                 done(new Error('packageJSON.parse succeeded, but should\'ve failed'));
             })
             .catch(function (err) {
-                err.message.should.equal('errors.utils.parsepackagejson.themeFileIsMalformed');
+                err.message.should.equal('Theme package.json file is malformed');
                 err.context.should.equal(tmpFile.name);
-                err.help.should.equal('errors.utils.parsepackagejson.willBeRequired');
+                err.help.should.equal('This will be required in future. Please see https://ghost.org/docs/themes/');
 
                 done();
             })
@@ -121,7 +117,7 @@ describe('lib/fs/package-json: parse', function () {
                 done(new Error('packageJSON.parse succeeded, but should\'ve failed'));
             })
             .catch(function (err) {
-                err.message.should.equal('errors.utils.parsepackagejson.couldNotReadPackage');
+                err.message.should.equal('Could not read package.json file');
                 err.context.should.equal(tmpFile.name);
 
                 done();
diff --git a/ghost/package-json/test/read.test.js b/ghost/package-json/test/read.test.js
index 7f2fceeeef..7ea9232c88 100644
--- a/ghost/package-json/test/read.test.js
+++ b/ghost/package-json/test/read.test.js
@@ -5,11 +5,7 @@ const join = require('path').join;
 const fs = require('fs-extra');
 const PackageJSON = require('../');
 
-const packageJSON = new PackageJSON({
-    i18n: {
-        t: key => key
-    }
-});
+const packageJSON = new PackageJSON();
 
 describe('lib/fs/package-json: read', function () {
     describe('all', function () {