diff --git a/app/src/Exceptions/InvalidConfiguration.php b/app/src/Exceptions/InvalidConfiguration.php
new file mode 100644
index 0000000..fce9a5e
--- /dev/null
+++ b/app/src/Exceptions/InvalidConfiguration.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Exceptions;
+
+use RuntimeException;
+
+class InvalidConfiguration extends RuntimeException
+{
+    /**
+     * Createn an exception from a configiraton option and value.
+     *
+     * @param string $option
+     * @param mixed  $value
+     *
+     * @return self
+     */
+    public static function fromConfig(string $option, $value): self
+    {
+        return new static(
+            sprintf("Unknown value %s for configuration option '%s'", var_export($value, true), $option)
+        );
+    }
+}
diff --git a/app/src/Factories/FinderFactory.php b/app/src/Factories/FinderFactory.php
index 31ffb85..d7e6e68 100644
--- a/app/src/Factories/FinderFactory.php
+++ b/app/src/Factories/FinderFactory.php
@@ -2,10 +2,10 @@
 
 namespace App\Factories;
 
+use App\Exceptions\InvalidConfiguration;
 use Closure;
 use DI\Container;
 use PHLAK\Splat\Glob;
-use RuntimeException;
 use Symfony\Component\Finder\Finder;
 use Symfony\Component\Finder\SplFileInfo;
 use Tightenco\Collect\Support\Collection;
@@ -46,7 +46,7 @@ class FinderFactory
             $finder->sort($sortOrder);
         } else {
             if (! array_key_exists($sortOrder, $this->container->get('sort_methods'))) {
-                throw new RuntimeException("Invalid sort option '{$sortOrder}'");
+                throw InvalidConfiguration::fromConfig('sort_order', $sortOrder);
             }
 
             $this->container->call($this->container->get('sort_methods')[$sortOrder], [$finder]);
diff --git a/app/src/Factories/TranslationFactory.php b/app/src/Factories/TranslationFactory.php
index f6220a8..d8fa96e 100644
--- a/app/src/Factories/TranslationFactory.php
+++ b/app/src/Factories/TranslationFactory.php
@@ -2,8 +2,8 @@
 
 namespace App\Factories;
 
+use App\Exceptions\InvalidConfiguration;
 use DI\Container;
-use RuntimeException;
 use Symfony\Component\Finder\Finder;
 use Symfony\Component\Finder\SplFileInfo;
 use Symfony\Component\Translation\Loader\YamlFileLoader;
@@ -37,16 +37,17 @@ class TranslationFactory
      */
     public function __invoke(): TranslatorInterface
     {
-        $language = $this->container->get('language');
-
-        if (! in_array($language, $this->container->get('translations'))) {
-            throw new RuntimeException("Invalid language option '{$language}'");
+        if (! in_array(
+            $language = $this->container->get('language'),
+            $translations = $this->translations())
+        ) {
+            throw InvalidConfiguration::fromConfig('language', $language);
         }
 
         $translator = new Translator($language);
         $translator->addLoader('yaml', new YamlFileLoader());
 
-        foreach ($this->container->get('translations') as $language) {
+        foreach ($translations as $language) {
             $translator->addResource('yaml', sprintf(
                 '%s/%s.yaml', $this->container->get('translations_path'), $language
             ), $language);
diff --git a/tests/Factories/FinderFactoryTest.php b/tests/Factories/FinderFactoryTest.php
index e6d404e..8c3c622 100644
--- a/tests/Factories/FinderFactoryTest.php
+++ b/tests/Factories/FinderFactoryTest.php
@@ -2,8 +2,8 @@
 
 namespace Tests\Factories;
 
+use App\Exceptions\InvalidConfiguration;
 use App\Factories\FinderFactory;
-use RuntimeException;
 use Symfony\Component\Finder\Finder;
 use Symfony\Component\Finder\SplFileInfo;
 use Tests\TestCase;
@@ -85,7 +85,7 @@ class FinderFactoryTest extends TestCase
     {
         $this->container->set('sort_order', 'invalid');
 
-        $this->expectException(RuntimeException::class);
+        $this->expectException(InvalidConfiguration::class);
 
         (new FinderFactory($this->container, $this->cache))();
     }
diff --git a/tests/Factories/TranslationFactoryTest.php b/tests/Factories/TranslationFactoryTest.php
index fc43537..076823d 100644
--- a/tests/Factories/TranslationFactoryTest.php
+++ b/tests/Factories/TranslationFactoryTest.php
@@ -2,8 +2,8 @@
 
 namespace Tests\Factories;
 
+use App\Exceptions\InvalidConfiguration;
 use App\Factories\TranslationFactory;
-use RuntimeException;
 use Symfony\Component\Translation\MessageCatalogue;
 use Tests\TestCase;
 
@@ -29,7 +29,7 @@ class TranslationFactoryTest extends TestCase
 
     public function test_it_throws_an_exception_for_an_invalid_language(): void
     {
-        $this->expectException(RuntimeException::class);
+        $this->expectException(InvalidConfiguration::class);
 
         $this->container->set('language', 'xx');
         (new TranslationFactory($this->container, $this->cache))();