diff --git a/activemodel/lib/active_model/validations/inclusion.rb b/activemodel/lib/active_model/validations/inclusion.rb
index 0c1334fe1b..c1838bb93e 100644
--- a/activemodel/lib/active_model/validations/inclusion.rb
+++ b/activemodel/lib/active_model/validations/inclusion.rb
@@ -4,7 +4,7 @@ module ActiveModel
       def check_validity!
          raise ArgumentError, "An object with the method include? is required must be supplied as the " <<
                               ":in option of the configuration hash" unless options[:in].respond_to?(:include?)
-       end
+      end
 
       def validate_each(record, attribute, value)
         return if options[:in].include?(value)