diff --git a/src/Jenssegers/Mongodb/Queue/Failed/MongoFailedJobProvider.php b/src/Jenssegers/Mongodb/Queue/Failed/MongoFailedJobProvider.php
index 9067a2838..d350bb032 100644
--- a/src/Jenssegers/Mongodb/Queue/Failed/MongoFailedJobProvider.php
+++ b/src/Jenssegers/Mongodb/Queue/Failed/MongoFailedJobProvider.php
@@ -12,12 +12,15 @@ class MongoFailedJobProvider extends DatabaseFailedJobProvider
      * @param string $connection
      * @param string $queue
      * @param string $payload
+     * @param  \Exception  $exception
      * @return void
      */
     public function log($connection, $queue, $payload, $exception)
     {
         $failed_at = Carbon::now()->getTimestamp();
 
+        $exception = (string) $exception;
+
         $this->getTable()->insert(compact('connection', 'queue', 'payload', 'failed_at', 'exception'));
     }