diff --git a/spec/AuthenticationAdapters.spec.js b/spec/AuthenticationAdapters.spec.js
index c6834dcf45..ae7e08be05 100644
--- a/spec/AuthenticationAdapters.spec.js
+++ b/spec/AuthenticationAdapters.spec.js
@@ -399,6 +399,33 @@ describe('AuthenticationProviders', function () {
     );
   });
 
+  it('should cache adapter', async () => {
+    const adapter = {
+      validateAppId() {
+        return Promise.resolve();
+      },
+      validateAuthData() {
+        return Promise.resolve();
+      },
+      validateOptions() {},
+    };
+
+    const authDataSpy = spyOn(adapter, 'validateAuthData').and.callThrough();
+    const optionsSpy = spyOn(adapter, 'validateOptions').and.callThrough();
+
+    await reconfigureServer({ auth: { customAuthentication: adapter } });
+
+    expect(optionsSpy).toHaveBeenCalled();
+    await Parse.User.logInWith('customAuthentication', {
+      authData: { id: 'user1', token: 'fakeToken1' },
+    });
+    await Parse.User.logInWith('customAuthentication', {
+      authData: { id: 'user2', token: 'fakeToken2' },
+    });
+    expect(authDataSpy).toHaveBeenCalled();
+    expect(optionsSpy).toHaveBeenCalledTimes(1);
+  });
+
   it('properly loads custom adapter module object', done => {
     const authenticationHandler = authenticationLoader({
       customAuthentication: path.resolve('./spec/support/CustomAuth.js'),
diff --git a/spec/AuthenticationAdaptersV2.spec.js b/spec/AuthenticationAdaptersV2.spec.js
index e9486187ef..a506852fbd 100644
--- a/spec/AuthenticationAdaptersV2.spec.js
+++ b/spec/AuthenticationAdaptersV2.spec.js
@@ -348,7 +348,9 @@ describe('Auth Adapter features', () => {
   it('should strip out authData if required', async () => {
     const spy = spyOn(modernAdapter3, 'validateOptions').and.callThrough();
     const afterSpy = spyOn(modernAdapter3, 'afterFind').and.callThrough();
-    await reconfigureServer({ auth: { modernAdapter3 } });
+    await reconfigureServer({ auth: { modernAdapter3 }, silent: false });
+    expect(spy).toHaveBeenCalled();
+    spy.calls.reset();
     const user = new Parse.User();
     await user.save({ authData: { modernAdapter3: { id: 'modernAdapter3Data' } } });
     await user.fetch({ sessionToken: user.getSessionToken() });
@@ -366,7 +368,7 @@ describe('Auth Adapter features', () => {
       { id: 'modernAdapter3Data' },
       undefined
     );
-    expect(spy).toHaveBeenCalled();
+    expect(spy).not.toHaveBeenCalled();
   });
 
   it('should throw if no triggers found', async () => {
@@ -1262,6 +1264,10 @@ describe('Auth Adapter features', () => {
 
     spyOn(challengeAdapter, 'validateAuthData').and.rejectWith({});
 
+    await reconfigureServer({
+      auth: { challengeAdapter, soloAdapter },
+    });
+
     await expectAsync(
       requestWithExpectedError({
         headers: headers,
diff --git a/spec/ParseUser.spec.js b/spec/ParseUser.spec.js
index e97db08a6c..42c73eeb4b 100644
--- a/spec/ParseUser.spec.js
+++ b/spec/ParseUser.spec.js
@@ -486,6 +486,19 @@ describe('Parse.User testing', () => {
       );
   });
 
+  it('cannot connect to unconfigured adapter', async () => {
+    await reconfigureServer({
+      auth: {},
+    });
+    const provider = getMockFacebookProvider();
+    Parse.User._registerAuthenticationProvider(provider);
+    const user = new Parse.User();
+    user.set('foo', 'bar');
+    await expectAsync(user._linkWith('facebook', {})).toBeRejectedWith(
+      new Parse.Error(Parse.Error.UNSUPPORTED_SERVICE, 'This authentication method is unsupported.')
+    );
+  });
+
   it('should not call beforeLogin with become', async done => {
     const provider = getMockFacebookProvider();
     Parse.User._registerAuthenticationProvider(provider);
diff --git a/src/Adapters/Auth/AuthAdapter.js b/src/Adapters/Auth/AuthAdapter.js
index e739df3f54..2ff1989fd6 100644
--- a/src/Adapters/Auth/AuthAdapter.js
+++ b/src/Adapters/Auth/AuthAdapter.js
@@ -102,16 +102,26 @@ export class AuthAdapter {
    * @param {Object} options additional adapter options
    * @returns {Promise<Object>} Any overrides required to authData
    */
-  afterFind(authData, options) {
-    return Promise.resolve({});
-  }
+  afterFind(authData, options) {}
 
   /**
    * Triggered when the adapter is first attached to Parse Server
    * @param {Object} options Adapter Options
    */
-  validateOptions(options) {
-    /* */
+  validateOptions(options) {}
+
+  _clearDefaultKeys(keys) {
+    const defaultAdapter = new AuthAdapter();
+    keys.forEach(key => {
+      const existing = this[key];
+      if (
+        existing &&
+        typeof existing === 'function' &&
+        existing.toString() === defaultAdapter[key].toString()
+      ) {
+        this[key] = null;
+      }
+    });
   }
 }
 
diff --git a/src/Adapters/Auth/index.js b/src/Adapters/Auth/index.js
index da65b24ba5..411d4f46dc 100755
--- a/src/Adapters/Auth/index.js
+++ b/src/Adapters/Auth/index.js
@@ -1,7 +1,6 @@
 import loadAdapter from '../AdapterLoader';
 import Parse from 'parse/node';
 import AuthAdapter from './AuthAdapter';
-
 const apple = require('./apple');
 const gcenter = require('./gcenter');
 const gpgames = require('./gpgames');
@@ -142,7 +141,6 @@ function authDataValidator(provider, adapter, appIds, options) {
 }
 
 function loadAuthAdapter(provider, authOptions) {
-  // providers are auth providers implemented by default
   let defaultAdapter = providers[provider];
   // authOptions can contain complete custom auth adapters or
   // a default auth adapter like Facebook
@@ -160,8 +158,6 @@ function loadAuthAdapter(provider, authOptions) {
     return;
   }
 
-  const adapter =
-    defaultAdapter instanceof AuthAdapter ? defaultAdapter : Object.assign({}, defaultAdapter);
   const keys = [
     'validateAuthData',
     'validateAppId',
@@ -173,20 +169,13 @@ function loadAuthAdapter(provider, authOptions) {
     'policy',
     'afterFind',
   ];
-  const defaultAuthAdapter = new AuthAdapter();
-  keys.forEach(key => {
-    const existing = adapter?.[key];
-    if (
-      existing &&
-      typeof existing === 'function' &&
-      existing.toString() === defaultAuthAdapter[key].toString()
-    ) {
-      adapter[key] = null;
-    }
-  });
-  const appIds = providerOptions ? providerOptions.appIds : undefined;
 
-  // Try the configuration methods
+  let adapter = Object.assign({}, defaultAdapter);
+  if (defaultAdapter instanceof AuthAdapter) {
+    adapter = new defaultAdapter.constructor();
+    defaultAdapter._clearDefaultKeys(keys);
+  }
+
   if (providerOptions) {
     const optionalAdapter = loadAdapter(providerOptions, undefined, providerOptions);
     if (optionalAdapter) {
@@ -197,25 +186,44 @@ function loadAuthAdapter(provider, authOptions) {
       });
     }
   }
-  if (adapter.validateOptions) {
-    adapter.validateOptions(providerOptions);
+
+  if (providerOptions?.enabled !== false) {
+    if (adapter.validateOptions) {
+      adapter.validateOptions(providerOptions);
+    }
   }
 
+  const appIds = providerOptions ? providerOptions.appIds : undefined;
   return { adapter, appIds, providerOptions };
 }
 
+function validateAuthConfig(auth) {
+  const authCache = new Map();
+  if (!auth.anonymous) {
+    auth.anonymous = { enabled: true };
+  }
+  Object.keys(auth).forEach(key => {
+    const authObject = loadAuthAdapter(key, auth);
+    authCache.set(key, authObject);
+  });
+  return authCache;
+}
+
 module.exports = function (authOptions = {}, enableAnonymousUsers = true) {
   let _enableAnonymousUsers = enableAnonymousUsers;
   const setEnableAnonymousUsers = function (enable) {
     _enableAnonymousUsers = enable;
   };
+  const authCache = validateAuthConfig(authOptions);
   // To handle the test cases on configuration
   const getValidatorForProvider = function (provider) {
     if (provider === 'anonymous' && !_enableAnonymousUsers) {
       return { validator: undefined };
     }
-    const authAdapter = loadAuthAdapter(provider, authOptions);
-    if (!authAdapter) return;
+    const authAdapter = authCache.get(provider);
+    if (!authAdapter) {
+      return { validator: undefined };
+    }
     const { adapter, appIds, providerOptions } = authAdapter;
     return { validator: authDataValidator(provider, adapter, appIds, providerOptions), adapter };
   };
@@ -257,6 +265,7 @@ module.exports = function (authOptions = {}, enableAnonymousUsers = true) {
     getValidatorForProvider,
     setEnableAnonymousUsers,
     runAfterFind,
+    authCache,
   });
 };
 
diff --git a/src/Auth.js b/src/Auth.js
index f21ba96c6c..5e10f5e1fa 100644
--- a/src/Auth.js
+++ b/src/Auth.js
@@ -528,6 +528,12 @@ const handleAuthDataValidation = async (authData, req, foundUser) => {
           'This authentication method is unsupported.'
         );
       }
+      if (authProvider.enabled == null) {
+        Deprecator.logRuntimeDeprecation({
+          usage: `Using the authentication adapter "${provider}" without explicitly enabling it`,
+          solution: `Enable the authentication adapter by setting the Parse Server option "auth.${provider}.enabled: true".`,
+        });
+      }
       let validationResult = await validator(authData[provider], req, user, requestObject);
       method = validationResult && validationResult.method;
       requestObject.triggerName = method;
diff --git a/src/Routers/UsersRouter.js b/src/Routers/UsersRouter.js
index 8af8dc5434..490a3d75a9 100644
--- a/src/Routers/UsersRouter.js
+++ b/src/Routers/UsersRouter.js
@@ -586,7 +586,7 @@ export class UsersRouter extends ClassesRouter {
     for (const provider of Object.keys(challengeData).sort()) {
       try {
         const authAdapter = req.config.authDataManager.getValidatorForProvider(provider);
-        if (!authAdapter) {
+        if (!authAdapter?.validator) {
           continue;
         }
         const {