diff --git a/activemodel/test/cases/validations/absence_validation_test.rb b/activemodel/test/cases/validations/absence_validation_test.rb
index c05d71de5a318aeda41a61ef60b1403882e85b09..795ce16d284518b2657f316be94a71844d42ea98 100644
--- a/activemodel/test/cases/validations/absence_validation_test.rb
+++ b/activemodel/test/cases/validations/absence_validation_test.rb
@@ -6,9 +6,9 @@
 
 class AbsenceValidationTest < ActiveModel::TestCase
   teardown do
-    Topic.reset_callbacks(:validate)
-    Person.reset_callbacks(:validate)
-    CustomReader.reset_callbacks(:validate)
+    Topic.clear_validators!
+    Person.clear_validators!
+    CustomReader.clear_validators!
   end
 
   def test_validate_absences
diff --git a/activemodel/test/cases/validations/acceptance_validation_test.rb b/activemodel/test/cases/validations/acceptance_validation_test.rb
index dc413bef300844a568c4e478a1a9d3c9145021df..d9d8c6b0f87381ade8f28d172d91d49c95b5f47a 100644
--- a/activemodel/test/cases/validations/acceptance_validation_test.rb
+++ b/activemodel/test/cases/validations/acceptance_validation_test.rb
@@ -8,7 +8,7 @@
 class AcceptanceValidationTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_terms_of_service_agreement_no_acceptance
diff --git a/activemodel/test/cases/validations/conditional_validation_test.rb b/activemodel/test/cases/validations/conditional_validation_test.rb
index 5049d6dd61351c410ee50832e770db67d06e659a..1261937b56334581bda02bdbf7b755b0c95840c2 100644
--- a/activemodel/test/cases/validations/conditional_validation_test.rb
+++ b/activemodel/test/cases/validations/conditional_validation_test.rb
@@ -6,7 +6,7 @@
 class ConditionalValidationTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_if_validation_using_method_true
diff --git a/activemodel/test/cases/validations/confirmation_validation_test.rb b/activemodel/test/cases/validations/confirmation_validation_test.rb
index f03de2c24ab64621427f385f7de9aff50cf87de0..4957ba5d0a4b9562a760c2f35ceac4233bcb778f 100644
--- a/activemodel/test/cases/validations/confirmation_validation_test.rb
+++ b/activemodel/test/cases/validations/confirmation_validation_test.rb
@@ -7,7 +7,7 @@
 class ConfirmationValidationTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_no_title_confirmation
@@ -49,7 +49,7 @@ def test_validates_confirmation_of_for_ruby_class
     p.karma = "None"
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 
   def test_title_confirmation_with_i18n_attribute
diff --git a/activemodel/test/cases/validations/exclusion_validation_test.rb b/activemodel/test/cases/validations/exclusion_validation_test.rb
index 81455ba5192e9d0a6f6cd5aadb3baf028e4af913..1ce41f9bc99ca01e4b7a4ebf260dadc631f7cc99 100644
--- a/activemodel/test/cases/validations/exclusion_validation_test.rb
+++ b/activemodel/test/cases/validations/exclusion_validation_test.rb
@@ -7,7 +7,7 @@
 class ExclusionValidationTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_validates_exclusion_of
@@ -50,7 +50,7 @@ def test_validates_exclusion_of_for_ruby_class
     p.karma = "Lifo"
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 
   def test_validates_exclusion_of_with_lambda
@@ -87,6 +87,6 @@ def p.reserved_karmas
 
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 end
diff --git a/activemodel/test/cases/validations/format_validation_test.rb b/activemodel/test/cases/validations/format_validation_test.rb
index 26e8dbf19c7e7b68ef070392dba51ffbc1fb6d6d..0f91b73cd7883d5a34e772bad254055b81f8e2e1 100644
--- a/activemodel/test/cases/validations/format_validation_test.rb
+++ b/activemodel/test/cases/validations/format_validation_test.rb
@@ -7,7 +7,7 @@
 class PresenceValidationTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_validate_format
@@ -68,11 +68,11 @@ def test_validate_format_with_formatted_message
     assert t.invalid?
     assert_equal ["can't be Invalid title"], t.errors[:title]
   end
-  
+
   def test_validate_format_of_with_multiline_regexp_should_raise_error
     assert_raise(ArgumentError) { Topic.validates_format_of(:title, with: /^Valid Title$/) }
   end
-  
+
   def test_validate_format_of_with_multiline_regexp_and_option
     assert_nothing_raised(ArgumentError) do
       Topic.validates_format_of(:title, with: /^Valid Title$/, multiline: true)
@@ -144,6 +144,6 @@ def test_validates_format_of_for_ruby_class
     p.karma = "1234"
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 end
diff --git a/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb b/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb
index 40a5aee9972dda9d32ee54931964998c2409ed48..93600c587a28c1ef376534f5f0f2e667ed7e68ec 100644
--- a/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb
+++ b/activemodel/test/cases/validations/i18n_generate_message_validation_test.rb
@@ -4,7 +4,7 @@
 
 class I18nGenerateMessageValidationTest < ActiveModel::TestCase
   def setup
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
     @person = Person.new
   end
 
diff --git a/activemodel/test/cases/validations/i18n_validation_test.rb b/activemodel/test/cases/validations/i18n_validation_test.rb
index e29771d6b7c9eac822e9fe9fbdbb0ede35023e1d..d10010537e961ec85768cc1a1466d6626e8b5587 100644
--- a/activemodel/test/cases/validations/i18n_validation_test.rb
+++ b/activemodel/test/cases/validations/i18n_validation_test.rb
@@ -6,7 +6,7 @@
 class I18nValidationTest < ActiveModel::TestCase
 
   def setup
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
     @person = Person.new
 
     @old_load_path, @old_backend = I18n.load_path.dup, I18n.backend
@@ -16,7 +16,7 @@ def setup
   end
 
   def teardown
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
     I18n.load_path.replace @old_load_path
     I18n.backend = @old_backend
   end
diff --git a/activemodel/test/cases/validations/inclusion_validation_test.rb b/activemodel/test/cases/validations/inclusion_validation_test.rb
index 8b908568698ccd33e426ba280e523e1d4cf1c79b..3a8f3080e1dd97aae2ea39803f784892d97c2a01 100644
--- a/activemodel/test/cases/validations/inclusion_validation_test.rb
+++ b/activemodel/test/cases/validations/inclusion_validation_test.rb
@@ -8,7 +8,7 @@
 class InclusionValidationTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_validates_inclusion_of_range
@@ -105,7 +105,7 @@ def test_validates_inclusion_of_for_ruby_class
     p.karma = "monkey"
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 
   def test_validates_inclusion_of_with_lambda
@@ -142,6 +142,6 @@ def p.available_karmas
 
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 end
diff --git a/activemodel/test/cases/validations/length_validation_test.rb b/activemodel/test/cases/validations/length_validation_test.rb
index 8b2f886cc46cf3ceef4640b4c72a35deb7200fb7..046ffcb16f3d707cb9a069ddb48ba3be5c17f69d 100644
--- a/activemodel/test/cases/validations/length_validation_test.rb
+++ b/activemodel/test/cases/validations/length_validation_test.rb
@@ -6,7 +6,7 @@
 
 class LengthValidationTest < ActiveModel::TestCase
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_validates_length_of_with_allow_nil
@@ -354,7 +354,7 @@ def test_validates_length_of_for_ruby_class
     p.karma = "The Smiths"
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 
   def test_validates_length_of_for_infinite_maxima
diff --git a/activemodel/test/cases/validations/numericality_validation_test.rb b/activemodel/test/cases/validations/numericality_validation_test.rb
index 84332ed0145f6d5e6745219a2d13645f1dfd523b..f77cf47fb71fe3df8c90c8d8d833ba204017d4f9 100644
--- a/activemodel/test/cases/validations/numericality_validation_test.rb
+++ b/activemodel/test/cases/validations/numericality_validation_test.rb
@@ -9,7 +9,7 @@
 class NumericalityValidationTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   NIL = [nil]
@@ -157,7 +157,7 @@ def test_validates_numericality_of_for_ruby_class
     p.karma = "1234"
     assert p.valid?
   ensure
-    Person.reset_callbacks(:validate)
+    Person.clear_validators!
   end
 
   def test_validates_numericality_with_invalid_args
diff --git a/activemodel/test/cases/validations/presence_validation_test.rb b/activemodel/test/cases/validations/presence_validation_test.rb
index 2f228cfa836fc4f298cca44b3fab2703c3c7456b..ecf16d1e1692313e1ad7691e6d6c6d29994f134d 100644
--- a/activemodel/test/cases/validations/presence_validation_test.rb
+++ b/activemodel/test/cases/validations/presence_validation_test.rb
@@ -8,9 +8,9 @@
 class PresenceValidationTest < ActiveModel::TestCase
 
   teardown do
-    Topic.reset_callbacks(:validate)
-    Person.reset_callbacks(:validate)
-    CustomReader.reset_callbacks(:validate)
+    Topic.clear_validators!
+    Person.clear_validators!
+    CustomReader.clear_validators!
   end
 
   def test_validate_presences
diff --git a/activemodel/test/cases/validations/validates_test.rb b/activemodel/test/cases/validations/validates_test.rb
index c1914b32bcbc8e6fe3813a07fa4cf38af6b9675b..699a872e423e58b01a69f9960e0c3e2ab20b8b68 100644
--- a/activemodel/test/cases/validations/validates_test.rb
+++ b/activemodel/test/cases/validations/validates_test.rb
@@ -11,9 +11,9 @@ class ValidatesTest < ActiveModel::TestCase
   teardown :reset_callbacks
 
   def reset_callbacks
-    Person.reset_callbacks(:validate)
-    Topic.reset_callbacks(:validate)
-    PersonWithValidator.reset_callbacks(:validate)
+    Person.clear_validators!
+    Topic.clear_validators!
+    PersonWithValidator.clear_validators!
   end
 
   def test_validates_with_messages_empty
diff --git a/activemodel/test/cases/validations/validations_context_test.rb b/activemodel/test/cases/validations/validations_context_test.rb
index 9ad20e8453dfc44fe1f949448cac9e8fa796ea72..005bf118c6cc494978e1b3f0c98f175e3711f314 100644
--- a/activemodel/test/cases/validations/validations_context_test.rb
+++ b/activemodel/test/cases/validations/validations_context_test.rb
@@ -5,8 +5,7 @@
 
 class ValidationsContextTest < ActiveModel::TestCase
   def teardown
-    Topic.reset_callbacks(:validate)
-    Topic._validators.clear
+    Topic.clear_validators!
   end
 
   ERROR_MESSAGE = "Validation error from validator"
diff --git a/activemodel/test/cases/validations/with_validation_test.rb b/activemodel/test/cases/validations/with_validation_test.rb
index 93716f14331ab7063b735e8b978995e25c181efe..736c2deea863b5401bf978f4edddcabf19c75ef2 100644
--- a/activemodel/test/cases/validations/with_validation_test.rb
+++ b/activemodel/test/cases/validations/with_validation_test.rb
@@ -6,8 +6,7 @@
 class ValidatesWithTest < ActiveModel::TestCase
 
   def teardown
-    Topic.reset_callbacks(:validate)
-    Topic._validators.clear
+    Topic.clear_validators!
   end
 
   ERROR_MESSAGE = "Validation error from validator"
diff --git a/activemodel/test/cases/validations_test.rb b/activemodel/test/cases/validations_test.rb
index 039b6b8872ef541e67034dcac36e64f7c7c2c3c7..bee8ece992fac714fcbadd15e2c88d605bd8bad1 100644
--- a/activemodel/test/cases/validations_test.rb
+++ b/activemodel/test/cases/validations_test.rb
@@ -10,17 +10,10 @@
 require 'active_support/xml_mini'
 
 class ValidationsTest < ActiveModel::TestCase
-
   class CustomStrictValidationException < StandardError; end
 
-  def setup
-    Topic._validators.clear
-  end
-
-  # Most of the tests mess with the validations of Topic, so lets repair it all the time.
-  # Other classes we mess with will be dealt with in the specific tests
   def teardown
-    Topic.reset_callbacks(:validate)
+    Topic.clear_validators!
   end
 
   def test_single_field_validation