diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2365ad9c..40c06e51 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Upgrade php cs fixer to latest ([#783](https://github.com/jsonrainbow/json-schema/pull/783))
 - Create deep copy before checking each sub schema in oneOf ([#791](https://github.com/jsonrainbow/json-schema/pull/791))
 - Create deep copy before checking each sub schema in anyOf ([#792](https://github.com/jsonrainbow/json-schema/pull/792))
+- Correctly set the schema ID when passing it as assoc array ([#794](https://github.com/jsonrainbow/json-schema/pull/794))
 
 ### Changed
 - Used PHPStan's int-mask-of<T> type where applicable ([#779](https://github.com/jsonrainbow/json-schema/pull/779))
diff --git a/src/JsonSchema/Constraints/TypeCheck/LooseTypeCheck.php b/src/JsonSchema/Constraints/TypeCheck/LooseTypeCheck.php
index 18057512..8f9f349b 100644
--- a/src/JsonSchema/Constraints/TypeCheck/LooseTypeCheck.php
+++ b/src/JsonSchema/Constraints/TypeCheck/LooseTypeCheck.php
@@ -44,7 +44,7 @@ public static function propertyExists($value, $property)
             return property_exists($value, $property);
         }
 
-        return array_key_exists($property, $value);
+        return is_array($value) && array_key_exists($property, $value);
     }
 
     public static function propertyCount($value)
diff --git a/src/JsonSchema/Validator.php b/src/JsonSchema/Validator.php
index a02c2e5d..bf172640 100644
--- a/src/JsonSchema/Validator.php
+++ b/src/JsonSchema/Validator.php
@@ -13,6 +13,7 @@
 
 use JsonSchema\Constraints\BaseConstraint;
 use JsonSchema\Constraints\Constraint;
+use JsonSchema\Constraints\TypeCheck\LooseTypeCheck;
 
 /**
  * A JsonSchema Constraint
@@ -59,10 +60,9 @@ public function validate(&$value, $schema = null, $checkMode = null)
         }
 
         // add provided schema to SchemaStorage with internal URI to allow internal $ref resolution
-        if (is_object($schema) && property_exists($schema, 'id')) {
-            $schemaURI = $schema->id;
-        } else {
-            $schemaURI = SchemaStorage::INTERNAL_PROVIDED_SCHEMA_URI;
+        $schemaURI = SchemaStorage::INTERNAL_PROVIDED_SCHEMA_URI;
+        if (LooseTypeCheck::propertyExists($schema, 'id')) {
+            $schemaURI = LooseTypeCheck::propertyGet($schema, 'id');
         }
         $this->factory->getSchemaStorage()->addSchema($schemaURI, $schema);
 
diff --git a/tests/ValidatorTest.php b/tests/ValidatorTest.php
index 26a8069d..9f536384 100644
--- a/tests/ValidatorTest.php
+++ b/tests/ValidatorTest.php
@@ -18,6 +18,17 @@ public function testValidateWithAssocSchema(): void
         $this->assertFalse($validator->isValid(), 'Validation succeeded, but should have failed.');
     }
 
+    public function testValidateWithAssocSchemaWithRelativeRefs(): void
+    {
+        $schema = json_decode(file_get_contents(__DIR__ . '/fixtures/relative.json'), true);
+        $data = json_decode('{"foo":{"foo": "bar"}}', false);
+
+        $validator = new Validator();
+        $validator->validate($data, $schema);
+
+        $this->assertTrue($validator->isValid(), 'Validation failed, but should have succeeded.');
+    }
+
     public function testBadAssocSchemaInput(): void
     {
         if (version_compare(phpversion(), '5.5.0', '<')) {
diff --git a/tests/fixtures/relative.json b/tests/fixtures/relative.json
new file mode 100644
index 00000000..f07531b2
--- /dev/null
+++ b/tests/fixtures/relative.json
@@ -0,0 +1,11 @@
+{
+    "id": "tests/fixtures/relative.json",
+    "type": "object",
+    "properties": {
+        "foo": {
+            "$ref": "foobar.json"
+        }
+    },
+    "required": ["foo"],
+    "additionalProperties": false
+}