diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8ab9341..1a74576 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,12 @@
 Change Log
 ==========
 
+2024-03-21
+----------
+
+ * fix callback strings as error messages (#26 thanks to [jakewhiteley](https://github.com/jakewhiteley)
+ * fix bug in callback binding in Callback rule, not setting scope to the rule instance
+
 2024-03-02
 ----------
 
diff --git a/README.md b/README.md
index 6c6532a..68b5f6a 100644
--- a/README.md
+++ b/README.md
@@ -372,7 +372,11 @@ $validation = $validator->validate($_POST, [
 ]);
 ```
 
-You can set a custom message by returning a string instead of false:
+You can set a custom message by returning a string instead of false. To allow for message translation, instead of
+a literal string; return a message key instead and add this to the message bag on the Factory.
+
+> Note: returning a message string will be removed in a future version, requiring only boolean responses.
+> Instead, set the message string directly before returning true/false via `$this->message = "";`.
 
 ```php
 $validation = $validator->validate($_POST, [
diff --git a/src/MessageBag.php b/src/MessageBag.php
index 2209bfd..5628ea0 100644
--- a/src/MessageBag.php
+++ b/src/MessageBag.php
@@ -61,4 +61,15 @@ public function has(string $key, string $lang = null): bool
     {
         return isset($this->messages[$lang ?? $this->defaultLang][$key]);
     }
+
+    public function hasAnyOf(array $keys, string $lang = null): bool
+    {
+        foreach ($keys as $key) {
+            if ($this->has($key, $lang)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
 }
diff --git a/src/Rules/Callback.php b/src/Rules/Callback.php
index 29809fc..fc8078b 100644
--- a/src/Rules/Callback.php
+++ b/src/Rules/Callback.php
@@ -28,7 +28,7 @@ public function check(mixed $value): bool
             throw new InvalidArgumentException(sprintf('Callback rule for "%s" is not callable.', $this->attribute->key()));
         }
 
-        $callback       = $callback->bindTo($this);
+        $callback       = $callback->bindTo($this, $this);
         $invalidMessage = $callback($value);
 
         if (is_string($invalidMessage)) {
diff --git a/src/Validation.php b/src/Validation.php
index f9c63d6..473cb7a 100644
--- a/src/Validation.php
+++ b/src/Validation.php
@@ -4,6 +4,7 @@
 
 use Closure;
 use Somnambulist\Components\Validation\Exceptions\RuleException;
+use Somnambulist\Components\Validation\Rules\Callback;
 use Somnambulist\Components\Validation\Rules\Contracts\ModifyValue;
 use Somnambulist\Components\Validation\Rules\Required;
 
@@ -361,7 +362,11 @@ protected function resolveMessage(Attribute $attribute, Rule $rule, mixed $value
             array_splice($messageKeys, 3, 0, $primaryAttributeKey);
         }
 
-        $message->setMessage($this->messages->firstOf($messageKeys, $this->lang));
+        $message->setMessage(
+            $this->messages->hasAnyOf($messageKeys, $this->lang)
+                ?
+                $this->messages->firstOf($messageKeys, $this->lang) : $message->key()
+        );
 
         // Replace key indexes
         $keyIndexes = $attribute->indexes();
diff --git a/tests/Issues/GH26HandlingCallbackErrorMessagesTest.php b/tests/Issues/GH26HandlingCallbackErrorMessagesTest.php
new file mode 100644
index 0000000..de7d519
--- /dev/null
+++ b/tests/Issues/GH26HandlingCallbackErrorMessagesTest.php
@@ -0,0 +1,58 @@
+<?php declare(strict_types=1);
+
+namespace Somnambulist\Components\Validation\Tests\Issues;
+
+use PHPUnit\Framework\TestCase;
+use Somnambulist\Components\Validation\Factory;
+
+class GH26HandlingCallbackErrorMessagesTest extends TestCase
+{
+    /**
+     * @link https://github.com/somnambulist-tech/validation/issues/26
+     */
+    public function testReturningMessageStringsProducesErrorMessage()
+    {
+        $testData = [
+            'name'   => 'John Doe',
+            'custom' => 'foo',
+        ];
+
+        $validation = (new Factory)->validate($testData, [
+            'name'   => 'required',
+            'custom' => [
+                'required',
+                function ($value) {
+                    if ($value !== 'bar') {
+                        return ':attribute should be bar';
+                    }
+
+                    return true;
+                },
+            ],
+        ]);
+
+        $this->assertEquals('custom should be bar', $validation->errors()->first('custom'));
+    }
+
+    public function testCanSetMessageIdentityViaCallback()
+    {
+        $testData = [
+            'name'   => 'John Doe',
+            'custom' => 'foo',
+        ];
+
+        $validation = (new Factory)->validate($testData, [
+            'name'   => 'required',
+            'custom' => [
+                'required',
+                function ($value) {
+                    $this->message = ':attribute should be bar';
+
+                    return $value === 'bar';
+                },
+            ],
+        ]);
+
+        $this->assertEquals('custom should be bar', $validation->errors()->first('custom'));
+    }
+}