diff --git a/objects/providers.py b/objects/providers.py
index 093e6f6b..fdf9b880 100644
--- a/objects/providers.py
+++ b/objects/providers.py
@@ -256,11 +256,13 @@ class Callable(Provider):
     with some predefined dependency injections.
     """
 
-    __slots__ = ('calls', 'injections')
+    __slots__ = ('callback', 'injections')
 
-    def __init__(self, calls, *injections):
+    def __init__(self, callback, *injections):
         """Initializer."""
-        self.calls = calls
+        if not callable(callback):
+            raise Error('Callable expected, got {}'.format(str(callback)))
+        self.callback = callback
         self.injections = tuple((injection
                                  for injection in injections
                                  if is_injection(injection)))
@@ -275,7 +277,7 @@ class Callable(Provider):
                            for injection in self.injections))
         injections.update(kwargs)
 
-        return self.calls(*args, **injections)
+        return self.callback(*args, **injections)
 
 
 class Config(Provider):
diff --git a/tests/test_providers.py b/tests/test_providers.py
index 1f7c7219..d74f2170 100644
--- a/tests/test_providers.py
+++ b/tests/test_providers.py
@@ -474,6 +474,10 @@ class CallableTests(unittest.TestCase):
                                  Injection('arg2', 'a2'),
                                  Injection('arg3', 'a3'))
 
+    def test_init_with_not_callable(self):
+        """Test creation of provider with not callable."""
+        self.assertRaises(Error, Callable, 123)
+
     def test_is_provider(self):
         """Test `is_provider` check."""
         self.assertTrue(is_provider(Callable(map)))
@@ -505,3 +509,12 @@ class CallableTests(unittest.TestCase):
 
         self.assertEqual(result1, (3, 2, 1))
         self.assertEqual(result2, (3, 2, 1))
+
+
+class ConfigTests(unittest.TestCase):
+
+    """Config test cases."""
+
+    def setUp(self):
+        """Set test cases environment up."""
+        self.provider = Config()