diff --git a/Gemfile b/Gemfile
index 3b38a5e..203c757 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ end
 
 group :test do
   gem "rspec"
-  gem "rubocop", "0.36.0"
+  gem "rubocop", "0.38.0"
   gem "coveralls", require: false
   gem "certificate_authority", require: false
 end
diff --git a/lib/rails/auth/acl.rb b/lib/rails/auth/acl.rb
index c4e6302..d98ff32 100644
--- a/lib/rails/auth/acl.rb
+++ b/lib/rails/auth/acl.rb
@@ -26,7 +26,7 @@ def initialize(acl, matchers: {})
 
         acl.each_with_index do |entry|
           resources = entry["resources"]
-          fail ParseError, "no 'resources' key present in entry: #{entry.inspect}" unless resources
+          raise ParseError, "no 'resources' key present in entry: #{entry.inspect}" unless resources
 
           predicates = parse_predicates(entry, matchers.merge(DEFAULT_MATCHERS))
 
@@ -73,8 +73,8 @@ def parse_predicates(entry, matchers)
           next if name == "resources"
 
           matcher_class = matchers[name.to_sym]
-          fail ArgumentError, "no matcher for #{name}" unless matcher_class
-          fail TypeError, "expected Class for #{name}" unless matcher_class.is_a?(Class)
+          raise ArgumentError, "no matcher for #{name}" unless matcher_class
+          raise TypeError, "expected Class for #{name}" unless matcher_class.is_a?(Class)
 
           predicates[name.freeze] = matcher_class.new(options.freeze).freeze
         end
diff --git a/lib/rails/auth/acl/matchers/allow_all.rb b/lib/rails/auth/acl/matchers/allow_all.rb
index f3f512e..cc51df3 100644
--- a/lib/rails/auth/acl/matchers/allow_all.rb
+++ b/lib/rails/auth/acl/matchers/allow_all.rb
@@ -6,7 +6,7 @@ module Matchers
         # Allows unauthenticated clients to access to a given resource
         class AllowAll
           def initialize(enabled)
-            fail ArgumentError, "enabled must be true/false" unless [true, false].include?(enabled)
+            raise ArgumentError, "enabled must be true/false" unless [true, false].include?(enabled)
             @enabled = enabled
           end
 
diff --git a/lib/rails/auth/acl/middleware.rb b/lib/rails/auth/acl/middleware.rb
index 91349a8..88a7906 100644
--- a/lib/rails/auth/acl/middleware.rb
+++ b/lib/rails/auth/acl/middleware.rb
@@ -15,14 +15,14 @@ def self.from_acl_config(app, **args)
         #
         # @return [Rails::Auth::ACL::Middleware] new ACL middleware instance
         def initialize(app, acl: nil)
-          fail ArgumentError, "no acl given" unless acl
+          raise ArgumentError, "no acl given" unless acl
 
           @app = app
           @acl = acl
         end
 
         def call(env)
-          fail NotAuthorizedError, "unauthorized request" unless @acl.match(env)
+          raise NotAuthorizedError, "unauthorized request" unless @acl.match(env)
           @app.call(env)
         end
       end
diff --git a/lib/rails/auth/acl/resource.rb b/lib/rails/auth/acl/resource.rb
index bbe5545..ff9d205 100644
--- a/lib/rails/auth/acl/resource.rb
+++ b/lib/rails/auth/acl/resource.rb
@@ -18,11 +18,11 @@ class Resource
         # @param [Hash] :predicates matchers for this resource
         #
         def initialize(options, predicates)
-          fail TypeError, "expected Hash for options"    unless options.is_a?(Hash)
-          fail TypeError, "expected Hash for predicates" unless predicates.is_a?(Hash)
+          raise TypeError, "expected Hash for options"    unless options.is_a?(Hash)
+          raise TypeError, "expected Hash for predicates" unless predicates.is_a?(Hash)
 
           unless (extra_keys = options.keys - VALID_OPTIONS).empty?
-            fail ParseError, "unrecognized key in ACL resource: #{extra_keys.first}"
+            raise ParseError, "unrecognized key in ACL resource: #{extra_keys.first}"
           end
 
           @http_methods = extract_methods(options["method"])
@@ -63,7 +63,7 @@ def extract_methods(methods)
           return nil if methods.include?("ALL")
 
           methods.each do |method|
-            fail ParseError, "invalid HTTP method: #{method}" unless HTTP_METHODS.include?(method)
+            raise ParseError, "invalid HTTP method: #{method}" unless HTTP_METHODS.include?(method)
           end
 
           methods.freeze
diff --git a/lib/rails/auth/credentials.rb b/lib/rails/auth/credentials.rb
index cdee4d8..00c7a3c 100644
--- a/lib/rails/auth/credentials.rb
+++ b/lib/rails/auth/credentials.rb
@@ -25,7 +25,7 @@ def credentials(env)
       def add_credential(env, type, credential)
         credentials = env[CREDENTIALS_ENV_KEY] ||= {}
 
-        fail ArgumentError, "credential #{type} already added to request" if credentials.key?(type)
+        raise ArgumentError, "credential #{type} already added to request" if credentials.key?(type)
         credentials[type] = credential
 
         env
diff --git a/lib/rails/auth/error_page/middleware.rb b/lib/rails/auth/error_page/middleware.rb
index 0c66a58..e3a949e 100644
--- a/lib/rails/auth/error_page/middleware.rb
+++ b/lib/rails/auth/error_page/middleware.rb
@@ -4,7 +4,7 @@ module ErrorPage
       # Render an error page in the event Rails::Auth::NotAuthorizedError is raised
       class Middleware
         def initialize(app, page_body: nil)
-          fail TypeError, "page_body must be a String" unless page_body.is_a?(String)
+          raise TypeError, "page_body must be a String" unless page_body.is_a?(String)
 
           @app       = app
           @page_body = page_body.freeze
diff --git a/lib/rails/auth/rspec/helper_methods.rb b/lib/rails/auth/rspec/helper_methods.rb
index 37f3e7f..062d7a5 100644
--- a/lib/rails/auth/rspec/helper_methods.rb
+++ b/lib/rails/auth/rspec/helper_methods.rb
@@ -30,7 +30,7 @@ def x509_certificate_hash(**args)
 
             # Warn if methods are improperly used
             unless path.chars[0] == "/"
-              fail ArgumentError, "expected #{path} to start with '/'"
+              raise ArgumentError, "expected #{path} to start with '/'"
             end
 
             env = {
diff --git a/lib/rails/auth/x509/certificate.rb b/lib/rails/auth/x509/certificate.rb
index 9f049e4..91cf54a 100644
--- a/lib/rails/auth/x509/certificate.rb
+++ b/lib/rails/auth/x509/certificate.rb
@@ -9,7 +9,7 @@ class Certificate
 
         def initialize(certificate)
           unless certificate.is_a?(OpenSSL::X509::Certificate)
-            fail TypeError, "expecting OpenSSL::X509::Certificate, got #{certificate.class}"
+            raise TypeError, "expecting OpenSSL::X509::Certificate, got #{certificate.class}"
           end
 
           @certificate = certificate.freeze
diff --git a/lib/rails/auth/x509/middleware.rb b/lib/rails/auth/x509/middleware.rb
index fd90ec1..79f641b 100644
--- a/lib/rails/auth/x509/middleware.rb
+++ b/lib/rails/auth/x509/middleware.rb
@@ -19,7 +19,7 @@ class Middleware
         #
         # @return [Rails::Auth::X509::Middleware] new X509 middleware instance
         def initialize(app, cert_filters: {}, ca_file: nil, truststore: nil, require_cert: false, logger: nil)
-          fail ArgumentError, "no ca_file given" unless ca_file
+          raise ArgumentError, "no ca_file given" unless ca_file
 
           @app          = app
           @logger       = logger
@@ -57,11 +57,11 @@ def extract_credential(env)
               return Rails::Auth::X509::Certificate.new(cert)
             else
               log("Verify FAILED", cert)
-              fail CertificateVerifyFailed, "verify failed: #{subject(cert)}" if @require_cert
+              raise CertificateVerifyFailed, "verify failed: #{subject(cert)}" if @require_cert
             end
           end
 
-          fail CertificateVerifyFailed, "no client certificate in request" if @require_cert
+          raise CertificateVerifyFailed, "no client certificate in request" if @require_cert
           nil
         end
 
diff --git a/spec/rails/auth/error_page/middleware_spec.rb b/spec/rails/auth/error_page/middleware_spec.rb
index ba26517..fc9f14a 100644
--- a/spec/rails/auth/error_page/middleware_spec.rb
+++ b/spec/rails/auth/error_page/middleware_spec.rb
@@ -15,7 +15,7 @@
   end
 
   context "access denied" do
-    let(:app) { ->(_env) { fail(Rails::Auth::NotAuthorizedError, "not authorized!") } }
+    let(:app) { ->(_env) { raise(Rails::Auth::NotAuthorizedError, "not authorized!") } }
 
     it "renders the error page" do
       code, _env, body = middleware.call(request)