diff --git a/railties/lib/rails/railtie/configuration.rb b/railties/lib/rails/railtie/configuration.rb
index e4368866a1..2c7b5bc048 100644
--- a/railties/lib/rails/railtie/configuration.rb
+++ b/railties/lib/rails/railtie/configuration.rb
@@ -31,26 +31,34 @@ module Rails
         app_generators(&block)
       end
 
+      # First configurable block to run. Called before any initializers are run.
       def before_configuration(&block)
         ActiveSupport.on_load(:before_configuration, :yield => true, &block)
       end
 
+      # Third configurable block to run. Does not run if config.cache_classes
+      # set to false.
       def before_eager_load(&block)
         ActiveSupport.on_load(:before_eager_load, :yield => true, &block)
       end
 
+      # Second configurable block to run. Called before frameworks initialize.
       def before_initialize(&block)
         ActiveSupport.on_load(:before_initialize, :yield => true, &block)
       end
 
+      # Last configurable block to run. Called after frameworks initialize.
       def after_initialize(&block)
         ActiveSupport.on_load(:after_initialize, :yield => true, &block)
       end
 
+      # Array of callbacks defined by #to_prepare.
       def to_prepare_blocks
         @@to_prepare_blocks ||= []
       end
 
+      # Defines generic callbacks to run before #after_initialize. Useful for
+      # Rails::Railtie subclasses.
       def to_prepare(&blk)
         to_prepare_blocks << blk if blk
       end