diff --git a/src/Fields/Validator.php b/src/Fields/Validator.php
index 59b5a4c556..baa4a53f18 100644
--- a/src/Fields/Validator.php
+++ b/src/Fields/Validator.php
@@ -99,7 +99,7 @@ private function fieldAttributes()
 
     private function parse($rule)
     {
-        if (! Str::contains($rule, '{')) {
+        if (! is_string($rule) || ! Str::contains($rule, '{')) {
             return $rule;
         }