diff --git a/lib/jekyll/tags/include.rb b/lib/jekyll/tags/include.rb
index 0184a6a4..2b0d82b4 100644
--- a/lib/jekyll/tags/include.rb
+++ b/lib/jekyll/tags/include.rb
@@ -2,20 +2,28 @@ module Jekyll
   module Tags
     class IncludeTag < Liquid::Tag
 
-      MATCHER = /([\w-]+)\s*=\s*(?:"([^"\\]*(?:\\.[^"\\]*)*)"|'([^'\\]*(?:\\.[^'\\]*)*)'|([\w\.-]+))/
+      SYNTAX_EXAMPLE = "{% include file.ext param='value' param2='value' %}"
+
+      VALID_SYNTAX = /([\w-]+)\s*=\s*(?:"([^"\\]*(?:\\.[^"\\]*)*)"|'([^'\\]*(?:\\.[^'\\]*)*)'|([\w\.-]+))/      
+
+      INCLUDES_DIR = '_includes'
 
       def initialize(tag_name, markup, tokens)
         super
         @file, @params = markup.strip.split(' ', 2);
+        validate_syntax
+      end
+
+      def validate_syntax
+        validate_file_name
+        validate_params if @params
       end
 
       def parse_params(context)
-        validate_syntax
-
         params = {}
         markup = @params
 
-        while match = MATCHER.match(markup) do
+        while match = VALID_SYNTAX.match(markup) do
           markup = markup[match.end(0)..-1]
 
           value = if match[2]
@@ -31,32 +39,49 @@ module Jekyll
         params
       end
 
-      # ensure the entire markup string from start to end is valid syntax, and params are separated by spaces
-      def validate_syntax
-        full_matcher = Regexp.compile('\A\s*(?:' + MATCHER.to_s + '(?=\s|\z)\s*)*\z')
-        unless @params =~ full_matcher
-          raise SyntaxError.new <<-eos
+      def validate_file_name
+        if @file !~ /^[a-zA-Z0-9_\/\.-]+$/ || @file =~ /\.\// || @file =~ /\/\./
+            raise ArgumentError.new <<-eos
+Invalid syntax for include tag. File contains invalid characters or sequences:
+
+	#{@file}
+
+Valid syntax:
+
+	#{SYNTAX_EXAMPLE}
+
+eos
+        end
+      end
+
+      def validate_params
+        full_valid_syntax = Regexp.compile('\A\s*(?:' + VALID_SYNTAX.to_s + '(?=\s|\z)\s*)*\z')
+        unless @params =~ full_valid_syntax
+          raise ArgumentError.new <<-eos
 Invalid syntax for include tag:
 
 	#{@params}
 
 Valid syntax:
 
-	{% include file.ext param='value' param2="value" %}
+	#{SYNTAX_EXAMPLE}
 
 eos
         end
       end
 
       def render(context)
-        includes_dir = File.join(context.registers[:site].source, '_includes')
-
-        if error = validate_file(includes_dir)
+        dir = File.join(context.registers[:site].source, INCLUDES_DIR)
+        if error = validate_dir(dir, context.registers[:site].safe)
           return error
         end
 
-        source = File.read(File.join(includes_dir, @file))
-        partial = Liquid::Template.parse(source)
+        file = File.join(dir, @file)
+        if error = validate_file(dir, context.registers[:site].safe)
+          return error
+        end
+
+        partial = Liquid::Template.parse(source(file))
 
         context.stack do
           context['include'] = parse_params(context) if @params
@@ -64,26 +89,28 @@ eos
         end
       end
 
-      def validate_file(includes_dir)
-        if File.symlink?(includes_dir)
-          return "Includes directory '#{includes_dir}' cannot be a symlink"
+      def validate_dir(dir, safe)
+        if File.symlink?(dir) && safe
+          "Includes directory '#{dir}' cannot be a symlink"
         end
+      end
 
-        if @file !~ /^[a-zA-Z0-9_\/\.-]+$/ || @file =~ /\.\// || @file =~ /\/\./
-          return "Include file '#{@file}' contains invalid characters or sequences"
-        end
-
-        file = File.join(includes_dir, @file)
+      def validate_file(file, safe)
         if !File.exists?(file)
-          return "Included file #{@file} not found in _includes directory"
-        elsif File.symlink?(file)
-          return "The included file '_includes/#{@file}' should not be a symlink"
+          "Included file '#{@file}' not found in '#{INCLUDES_DIR}' directory"
+        elsif File.symlink?(file) && safe
+          "The included file '#{INCLUDES_DIR}/#{@file}' should not be a symlink"
         end
       end
 
       def blank?
         false
       end
+
+      # This method allows to modify the file content by inheriting from the class.
+      def source(file)
+        File.read(file)
+      end
     end
   end
 end
diff --git a/test/test_tags.rb b/test/test_tags.rb
index 5e25c1db..c58c9c7e 100644
--- a/test/test_tags.rb
+++ b/test/test_tags.rb
@@ -373,7 +373,7 @@ CONTENT
     end
 
     context "with invalid parameter syntax" do
-      should "throw a SyntaxError" do
+      should "throw a ArgumentError" do
         content = <<CONTENT
 ---
 title: Invalid parameter syntax
@@ -381,7 +381,7 @@ title: Invalid parameter syntax
 
 {% include params.html param s="value" %}
 CONTENT
-        assert_raise SyntaxError, 'Did not raise exception on invalid "include" syntax' do
+        assert_raise ArgumentError, 'Did not raise exception on invalid "include" syntax' do
           create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
         end
 
@@ -392,7 +392,7 @@ title: Invalid parameter syntax
 
 {% include params.html params="value %}
 CONTENT
-        assert_raise SyntaxError, 'Did not raise exception on invalid "include" syntax' do
+        assert_raise ArgumentError, 'Did not raise exception on invalid "include" syntax' do
           create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
         end
       end