diff --git a/bumpversion/__init__.py b/bumpversion/__init__.py
index c6f53cf..cfbf4ee 100644
--- a/bumpversion/__init__.py
+++ b/bumpversion/__init__.py
@@ -952,7 +952,6 @@ def main(original_args=None):
     vcs_context.update(prefixed_environ())
     vcs_context.update({'current_' + part: current_version[part].value for part in current_version})
     vcs_context.update({'new_' + part: new_version[part].value for part in new_version})
-    vcs_context.update({part: new_version[part].value for part in new_version})
 
     commit_message = args.message.format(**vcs_context)