diff --git a/src/Illuminate/Foundation/helpers.php b/src/Illuminate/Foundation/helpers.php
index 7b108491ae31..5688dced0fea 100644
--- a/src/Illuminate/Foundation/helpers.php
+++ b/src/Illuminate/Foundation/helpers.php
@@ -231,15 +231,19 @@ function cache()
             return app('cache')->get($arguments[0], isset($arguments[1]) ? $arguments[1] : null);
         }
 
-        if (is_array($arguments[0])) {
-            if (! isset($arguments[1])) {
-                throw new Exception(
-                    'You must set an expiration time when putting to the cache.'
-                );
-            }
+        if (! is_array($arguments[0])) {
+            throw new Exception(
+                'The argument passed to the cache must be a string or an array.'
+            );
+        }
 
-            return app('cache')->put(key($arguments[0]), reset($arguments[0]), $arguments[1]);
+        if (! isset($arguments[1])) {
+            throw new Exception(
+                'You must set an expiration time when putting to the cache.'
+            );
         }
+
+        return app('cache')->put(key($arguments[0]), reset($arguments[0]), $arguments[1]);
     }
 }