diff --git a/Parsedown.php b/Parsedown.php
index c8c92a3..b0e7094 100644
--- a/Parsedown.php
+++ b/Parsedown.php
@@ -115,7 +115,7 @@ class Parsedown
     # Blocks
     #
 
-    private function lines(array $lines)
+    protected function lines(array $lines)
     {
         $CurrentBlock = null;