diff --git a/core/lib/Drupal/Core/Config/Config.php b/core/lib/Drupal/Core/Config/Config.php
index 59dbad3..bf0973a 100644
--- a/core/lib/Drupal/Core/Config/Config.php
+++ b/core/lib/Drupal/Core/Config/Config.php
@@ -89,6 +89,8 @@ class Config {
    *   The configuration context used for this configuration object.
    */
   public function __construct($name, StorageInterface $storage, ContextInterface $context) {
+    // Validate the configuration object name.
+    static::validateName($name);
     $this->name = $name;
     $this->storage = $storage;
     $this->context = $context;
@@ -146,6 +148,8 @@ class Config {
    *   The configuration object.
    */
   public function setName($name) {
+    // Validate the configuration object name.
+    static::validateName($name);
     $this->name = $name;
     return $this;
   }
@@ -153,6 +157,11 @@ class Config {
   /**
    * Validates the configuration object name.
    *
+   * A valid name must:
+   * - Be namespaced by its owner (i.e. contain at least one '.').
+   * - Be shorter than Config::MAX_NAME_LENGTH characters.
+   * - Not contain any of the following characters:  ? : * < > " ' / \
+   *
    * @param string $name
    *  The name of the configuration object.
    *
@@ -161,7 +170,7 @@ class Config {
    * @see Config::MAX_NAME_LENGTH
    */
   public static function validateName($name) {
-    // The name must be namespaced by owner.
+    // The name must be namespaced by its owner.
     if (strpos($name, '.') === FALSE) {
       throw new ConfigNameException(format_string('Missing namespace in Config object name @name.', array(
         '@name' => $name,
@@ -404,8 +413,6 @@ class Config {
    *   The configuration object.
    */
   public function save() {
-    // Validate the configuration object name before saving.
-    static::validateName($this->name);
     if (!$this->isLoaded) {
       $this->load();
     }