diff --git a/AUTHORS.rst b/AUTHORS.rst
index fd129bb8f72..8d3e87ef22e 100644
--- a/AUTHORS.rst
+++ b/AUTHORS.rst
@@ -56,6 +56,7 @@ Contributors
 * Erik Bedard -- config options for :mod:`sphinx.ext.duration`
 * Etienne Desautels -- apidoc module
 * Ezio Melotti -- collapsible sidebar JavaScript
+* Fazeel Usmani -- parser API fixes
 * Filip Vavera -- napoleon todo directive
 * Florian Best -- log improvements
 * Glenn Matthews -- python domain signature improvements
diff --git a/CHANGES.rst b/CHANGES.rst
index 6f7279e8011..17b1a781084 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,3 +1,16 @@
+Release 9.2.0 (in development)
+==============================
+
+Deprecated
+----------
+
+* #14371: Un-deprecate :py:attr:`!Parser.config` and :py:attr:`!Parser.env`.
+  These remain the supported way for a custom parser to read the build
+  configuration and environment.
+  :py:meth:`!Parser.set_application` continues to be deprecated and is
+  scheduled for removal in Sphinx 10.
+  Patch by Fazeel Usmani.
+
 Release 9.1.0 (released Dec 31, 2025)
 =====================================
 
diff --git a/doc/extdev/parserapi.rst b/doc/extdev/parserapi.rst
index b5480996065..f9347a34dc7 100644
--- a/doc/extdev/parserapi.rst
+++ b/doc/extdev/parserapi.rst
@@ -36,3 +36,36 @@ to configure their settings appropriately.
 
 .. autoclass:: Parser
    :members:
+
+Accessing the Sphinx config and environment
+-------------------------------------------
+
+A custom parser can read Sphinx :class:`~sphinx.config.Config` values and the
+:class:`~sphinx.environment.BuildEnvironment` through the inherited
+``Parser.config`` and ``Parser.env`` properties.  Sphinx populates the
+backing ``_config`` and ``_env`` attributes when it instantiates a parser
+registered via :meth:`.Sphinx.add_source_parser`, so they are available
+from the start of ``parse()``.
+
+.. code-block:: python
+
+   from sphinx.parsers import Parser
+
+
+   class MyParser(Parser):
+       supported = ('mytype',)
+
+       def parse(self, inputstring, document):
+           # ``self.config`` and ``self.env`` are populated by Sphinx
+           encoding = self.config.source_encoding
+           docname = self.env.docname
+           ...
+
+.. versionchanged:: 9.2
+   ``Parser.config`` and ``Parser.env`` are no longer deprecated.
+
+.. deprecated:: 9.0
+   The ``Parser.set_application`` hook is deprecated and will be removed in
+   Sphinx 10.  Sphinx now populates ``_config`` and ``_env`` directly when
+   the parser instance is created, so custom parsers no longer need to
+   override ``set_application`` to capture these objects.
diff --git a/sphinx/parsers.py b/sphinx/parsers.py
index 5731ccd6f66..70abe8ac8c3 100644
--- a/sphinx/parsers.py
+++ b/sphinx/parsers.py
@@ -36,24 +36,40 @@ class Parser(docutils.parsers.Parser):
 
     @property
     def config(self) -> Config:
-        """The config object."""
-        cls_module = self.__class__.__module__
-        cls_name = self.__class__.__qualname__
-        _deprecation_warning(cls_module, f'{cls_name}.config', remove=(10, 0))
+        """The config object.
+
+        Populated by Sphinx when it instantiates a parser registered via
+        :meth:`.Sphinx.add_source_parser`, so this is available from the
+        start of ``parse()``.
+
+        .. versionchanged:: 9.2
+           No longer deprecated.
+        """
         return self._config
 
     @property
     def env(self) -> BuildEnvironment:
-        """The environment object."""
-        cls_module = self.__class__.__module__
-        cls_name = self.__class__.__qualname__
-        _deprecation_warning(cls_module, f'{cls_name}.env', remove=(10, 0))
+        """The environment object.
+
+        Populated by Sphinx when it instantiates a parser registered via
+        :meth:`.Sphinx.add_source_parser`, so this is available from the
+        start of ``parse()``.
+
+        .. versionchanged:: 9.2
+           No longer deprecated.
+        """
         return self._env
 
     def set_application(self, app: Sphinx) -> None:
-        """set_application will be called from Sphinx to set app and other instance variables
+        """Legacy compatibility hook for receiving the Sphinx application.
 
         :param sphinx.application.Sphinx app: Sphinx application object
+
+        .. deprecated:: 9.0
+           Sphinx now makes ``config`` and ``env`` available on the parser
+           instance automatically, so custom parsers no longer need to
+           override this method to capture the application.  It will be
+           removed in Sphinx 10.
         """
         cls_module = self.__class__.__module__
         cls_name = self.__class__.__qualname__
diff --git a/tests/test_markup/test_parser.py b/tests/test_markup/test_parser.py
index 215fdf04dd6..34ae11be8ba 100644
--- a/tests/test_markup/test_parser.py
+++ b/tests/test_markup/test_parser.py
@@ -2,12 +2,14 @@
 
 from __future__ import annotations
 
+import warnings
 from typing import TYPE_CHECKING
 from unittest.mock import Mock, patch
 
 import pytest
 
-from sphinx.parsers import RSTParser
+from sphinx.deprecation import RemovedInSphinx10Warning
+from sphinx.parsers import Parser, RSTParser
 from sphinx.util.docutils import new_document
 
 if TYPE_CHECKING:
@@ -68,3 +70,36 @@ def test_RSTParser_prolog_epilog(RSTStateMachine: Mock, app: SphinxTestApp) -> N
         ('dummy.rst', 0, '        hello Sphinx world'),
         ('dummy.rst', 1, '  Sphinx is a document generator'),
     ]
+
+
+@pytest.mark.sphinx('html', testroot='basic')
+def test_parser_config_env_populated_by_registry(app: SphinxTestApp) -> None:
+    """Parsers built via the registry expose config/env without warning (#14371).
+
+    This goes through the real construction path in
+    :meth:`.SphinxComponentRegistry.create_source_parser` so a regression in
+    that code path (for example, removal of the ``isinstance(..., SphinxParser)``
+    gate) would be caught here.
+    """
+    parser = app.registry.create_source_parser(
+        'restructuredtext', config=app.config, env=app.env
+    )
+    # ``create_source_parser`` is typed as ``docutils.parsers.Parser``; narrow
+    # to the Sphinx base class so ``config`` / ``env`` access type-checks and
+    # so a future regression that stops wrapping Sphinx parsers is caught here.
+    assert isinstance(parser, Parser)
+
+    with warnings.catch_warnings():
+        warnings.simplefilter('error', RemovedInSphinx10Warning)
+        assert parser.config is app.config
+        assert parser.env is app.env
+
+
+@pytest.mark.sphinx('html', testroot='basic')
+def test_parser_set_application_still_deprecated(app: SphinxTestApp) -> None:
+    """``Parser.set_application`` must still emit a deprecation warning (#14371)."""
+    parser = RSTParser()
+    with pytest.warns(RemovedInSphinx10Warning, match='set_application'):
+        parser.set_application(app)
+    assert parser.config is app.config
+    assert parser.env is app.env