diff --git a/spec/rspec/rails/configuration_spec.rb b/spec/rspec/rails/configuration_spec.rb
index a2b2dd09d..fdac679a2 100644
--- a/spec/rspec/rails/configuration_spec.rb
+++ b/spec/rspec/rails/configuration_spec.rb
@@ -123,7 +123,7 @@
     end
   end
 
-  describe "#infer_spec_type_from_file_location!" do
+  describe "#infer_spec_type_from_file_location!", :with_isolated_config do
     def in_inferring_type_from_location_environment
       in_sub_process do
         RSpec.configuration.infer_spec_type_from_file_location!
diff --git a/spec/rspec/rails/example/channel_example_group_spec.rb b/spec/rspec/rails/example/channel_example_group_spec.rb
index 642173364..4dccc8eab 100644
--- a/spec/rspec/rails/example/channel_example_group_spec.rb
+++ b/spec/rspec/rails/example/channel_example_group_spec.rb
@@ -1,7 +1,7 @@
 require "rspec/rails/feature_check"
 
 module RSpec::Rails
-  RSpec.describe ChannelExampleGroup do
+  RSpec.describe ChannelExampleGroup, :with_isolated_config do
     if RSpec::Rails::FeatureCheck.has_action_cable_testing?
       it_behaves_like "an rspec-rails example group mixin", :channel,
                       './spec/channels/', '.\\spec\\channels\\'
diff --git a/spec/rspec/rails/example/controller_example_group_spec.rb b/spec/rspec/rails/example/controller_example_group_spec.rb
index d50e88ae5..19ed6c07c 100644
--- a/spec/rspec/rails/example/controller_example_group_spec.rb
+++ b/spec/rspec/rails/example/controller_example_group_spec.rb
@@ -3,7 +3,7 @@ def self.abstract?; false; end
 end
 
 module RSpec::Rails
-  RSpec.describe ControllerExampleGroup do
+  RSpec.describe ControllerExampleGroup, :with_isolated_config do
     it_behaves_like "an rspec-rails example group mixin", :controller,
                     './spec/controllers/', '.\\spec\\controllers\\'
 
diff --git a/spec/rspec/rails/example/feature_example_group_spec.rb b/spec/rspec/rails/example/feature_example_group_spec.rb
index 35ccbcf72..f84de38ee 100644
--- a/spec/rspec/rails/example/feature_example_group_spec.rb
+++ b/spec/rspec/rails/example/feature_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe FeatureExampleGroup do
+  RSpec.describe FeatureExampleGroup, :with_isolated_config do
     it_behaves_like "an rspec-rails example group mixin", :feature,
                     './spec/features/', '.\\spec\\features\\'
 
diff --git a/spec/rspec/rails/example/helper_example_group_spec.rb b/spec/rspec/rails/example/helper_example_group_spec.rb
index 27b18ca33..d358261f4 100644
--- a/spec/rspec/rails/example/helper_example_group_spec.rb
+++ b/spec/rspec/rails/example/helper_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe HelperExampleGroup do
+  RSpec.describe HelperExampleGroup, :with_isolated_config do
     module ::FoosHelper
       class InternalClass
       end
diff --git a/spec/rspec/rails/example/job_example_group_spec.rb b/spec/rspec/rails/example/job_example_group_spec.rb
index fff75d493..dbc135715 100644
--- a/spec/rspec/rails/example/job_example_group_spec.rb
+++ b/spec/rspec/rails/example/job_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe JobExampleGroup do
+  RSpec.describe JobExampleGroup, :with_isolated_config do
     if defined?(ActiveJob)
       it_behaves_like "an rspec-rails example group mixin", :job,
                       './spec/jobs/', '.\\spec\\jobs\\'
diff --git a/spec/rspec/rails/example/mailbox_example_group_spec.rb b/spec/rspec/rails/example/mailbox_example_group_spec.rb
index 09793b2e7..9a6c43d36 100644
--- a/spec/rspec/rails/example/mailbox_example_group_spec.rb
+++ b/spec/rspec/rails/example/mailbox_example_group_spec.rb
@@ -14,7 +14,7 @@ def receive(*)
 
 module RSpec
   module Rails
-    RSpec.describe MailboxExampleGroup, skip: !RSpec::Rails::FeatureCheck.has_action_mailbox? do
+    RSpec.describe MailboxExampleGroup, :with_isolated_config, skip: !RSpec::Rails::FeatureCheck.has_action_mailbox? do
       it_behaves_like "an rspec-rails example group mixin", :mailbox,
                       './spec/mailboxes/', '.\\spec\\mailboxes\\'
 
diff --git a/spec/rspec/rails/example/mailer_example_group_spec.rb b/spec/rspec/rails/example/mailer_example_group_spec.rb
index 7baa327c8..5f558e27b 100644
--- a/spec/rspec/rails/example/mailer_example_group_spec.rb
+++ b/spec/rspec/rails/example/mailer_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe MailerExampleGroup do
+  RSpec.describe MailerExampleGroup, :with_isolated_config do
     module ::Rails; end
     before do
       allow(Rails).to receive_message_chain(:application, :routes, :url_helpers).and_return(Rails)
diff --git a/spec/rspec/rails/example/model_example_group_spec.rb b/spec/rspec/rails/example/model_example_group_spec.rb
index e496f1054..71dd62994 100644
--- a/spec/rspec/rails/example/model_example_group_spec.rb
+++ b/spec/rspec/rails/example/model_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe ModelExampleGroup do
+  RSpec.describe ModelExampleGroup, :with_isolated_config do
     it_behaves_like "an rspec-rails example group mixin", :model,
                     './spec/models/', '.\\spec\\models\\'
   end
diff --git a/spec/rspec/rails/example/rails_example_group_spec.rb b/spec/rspec/rails/example/rails_example_group_spec.rb
index d21dc2c3b..a4ded3f55 100644
--- a/spec/rspec/rails/example/rails_example_group_spec.rb
+++ b/spec/rspec/rails/example/rails_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe RailsExampleGroup do
+  RSpec.describe RailsExampleGroup, :with_isolated_config do
     it 'supports tagged_logger' do
       expect(described_class.private_instance_methods).to include(:tagged_logger)
     end
diff --git a/spec/rspec/rails/example/request_example_group_spec.rb b/spec/rspec/rails/example/request_example_group_spec.rb
index f8d3ef5f0..bcee23d01 100644
--- a/spec/rspec/rails/example/request_example_group_spec.rb
+++ b/spec/rspec/rails/example/request_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe RequestExampleGroup do
+  RSpec.describe RequestExampleGroup, :with_isolated_config do
     it_behaves_like "an rspec-rails example group mixin", :request,
                     './spec/requests/', '.\\spec\\requests\\',
                     './spec/integration/', '.\\spec\\integration\\',
diff --git a/spec/rspec/rails/example/routing_example_group_spec.rb b/spec/rspec/rails/example/routing_example_group_spec.rb
index 8ead44c39..2ccd65954 100644
--- a/spec/rspec/rails/example/routing_example_group_spec.rb
+++ b/spec/rspec/rails/example/routing_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe RoutingExampleGroup do
+  RSpec.describe RoutingExampleGroup, :with_isolated_config do
     it_behaves_like "an rspec-rails example group mixin", :routing,
                     './spec/routing/', '.\\spec\\routing\\'
 
diff --git a/spec/rspec/rails/example/system_example_group_spec.rb b/spec/rspec/rails/example/system_example_group_spec.rb
index bba10512d..274366052 100644
--- a/spec/rspec/rails/example/system_example_group_spec.rb
+++ b/spec/rspec/rails/example/system_example_group_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe SystemExampleGroup do
+  RSpec.describe SystemExampleGroup, :with_isolated_config do
     it_behaves_like "an rspec-rails example group mixin", :system,
                     './spec/system/', '.\\spec\\system\\'
 
diff --git a/spec/rspec/rails/example/view_example_group_spec.rb b/spec/rspec/rails/example/view_example_group_spec.rb
index 7dd0b3fec..106b7ae05 100644
--- a/spec/rspec/rails/example/view_example_group_spec.rb
+++ b/spec/rspec/rails/example/view_example_group_spec.rb
@@ -1,7 +1,7 @@
 require 'support/group_failure_formatter'
 
 module RSpec::Rails
-  RSpec.describe ViewExampleGroup do
+  RSpec.describe ViewExampleGroup, :with_isolated_config do
     it_behaves_like "an rspec-rails example group mixin", :view,
                     './spec/views/', '.\\spec\\views\\'
 
diff --git a/spec/rspec/rails/fixture_file_upload_support_spec.rb b/spec/rspec/rails/fixture_file_upload_support_spec.rb
index d28e29d32..ea26fe65d 100644
--- a/spec/rspec/rails/fixture_file_upload_support_spec.rb
+++ b/spec/rspec/rails/fixture_file_upload_support_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe FixtureFileUploadSupport do
+  RSpec.describe FixtureFileUploadSupport, :with_isolated_config do
     context 'with fixture paths set in config' do
       it 'resolves fixture file' do
         RSpec.configuration.fixture_paths = [File.dirname(__FILE__)]
diff --git a/spec/rspec/rails/fixture_support_spec.rb b/spec/rspec/rails/fixture_support_spec.rb
index 8621b5da5..1094486f0 100644
--- a/spec/rspec/rails/fixture_support_spec.rb
+++ b/spec/rspec/rails/fixture_support_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe FixtureSupport do
+  RSpec.describe FixtureSupport, :with_isolated_config do
     context "with use_transactional_fixtures set to false" do
       it "still supports fixture_path/fixture_paths" do
         allow(RSpec.configuration).to receive(:use_transactional_fixtures) { false }
diff --git a/spec/rspec/rails/matchers/have_http_status_spec.rb b/spec/rspec/rails/matchers/have_http_status_spec.rb
index 82333c74c..dfb8a301b 100644
--- a/spec/rspec/rails/matchers/have_http_status_spec.rb
+++ b/spec/rspec/rails/matchers/have_http_status_spec.rb
@@ -502,6 +502,7 @@ def create_response(opts = {})
 
   context 'with deprecated rack status codes' do
     it 'supports the original names' do
+      allow(Rack::Utils).to receive(:warn).with(/unprocessable_entity is deprecated/, anything)
       expect(create_response(status: 422)).to have_http_status(:unprocessable_entity)
     end
   end
diff --git a/spec/rspec/rails/minitest_lifecycle_adapter_spec.rb b/spec/rspec/rails/minitest_lifecycle_adapter_spec.rb
index 5c52d0c46..13e950dfd 100644
--- a/spec/rspec/rails/minitest_lifecycle_adapter_spec.rb
+++ b/spec/rspec/rails/minitest_lifecycle_adapter_spec.rb
@@ -1,4 +1,4 @@
-RSpec.describe RSpec::Rails::MinitestLifecycleAdapter do
+RSpec.describe RSpec::Rails::MinitestLifecycleAdapter, :with_isolated_config do
   it "invokes minitest lifecycle hooks at the appropriate times" do
     invocations = []
     example_group = RSpec::Core::ExampleGroup.describe("MinitestHooks") do
diff --git a/spec/rspec/rails/setup_and_teardown_adapter_spec.rb b/spec/rspec/rails/setup_and_teardown_adapter_spec.rb
index c6b515b22..8f8271da4 100644
--- a/spec/rspec/rails/setup_and_teardown_adapter_spec.rb
+++ b/spec/rspec/rails/setup_and_teardown_adapter_spec.rb
@@ -1,4 +1,4 @@
-RSpec.describe RSpec::Rails::SetupAndTeardownAdapter do
+RSpec.describe RSpec::Rails::SetupAndTeardownAdapter, :with_isolated_config do
   describe ".setup" do
     it "registers before hooks in the order setup is received" do
       group = RSpec::Core::ExampleGroup.describe do
diff --git a/spec/rspec/rails/view_rendering_spec.rb b/spec/rspec/rails/view_rendering_spec.rb
index 3273f2015..9ebefaf1d 100644
--- a/spec/rspec/rails/view_rendering_spec.rb
+++ b/spec/rspec/rails/view_rendering_spec.rb
@@ -1,5 +1,5 @@
 module RSpec::Rails
-  RSpec.describe ViewRendering do
+  RSpec.describe ViewRendering, :with_isolated_config do
     let(:group) do
       RSpec::Core::ExampleGroup.describe do
         def controller
@@ -53,7 +53,7 @@ def example.controller
           expect(group.new.render_views?).to be_falsey
         end
 
-        it "overrides the global config if render_views is enabled there" do
+        it "overrides the global config if render_views is enabled there", :with_isolated_config do
           allow(RSpec.configuration).to receive(:render_views?).and_return true
           group.render_views false
           expect(group.new.render_views?).to be_falsey
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 570f4cd12..f91c50f22 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -71,9 +71,11 @@ def self.run_all(reporter = nil)
   config.warnings = true
   config.raise_on_warning = true
 
+  config.raise_errors_for_deprecations!
+
   # Execute a provided block with RSpec global objects (configuration,
   # world, current example) reset. This is used to test specs with RSpec.
-  config.around(:example) do |example|
+  config.around(:example, :with_isolated_config) do |example|
     RSpec::Core::Sandbox.sandboxed do |sandbox_config|
       # If there is an example-within-an-example, we want to make sure the inner
       # example does not get a reference to the outer example (the real spec) if