An error has occurred

Warning: Constant DOWN already defined in /home/public/e-bible.app/app/app.php line 33

[1] file: /home/public/e-bible.app/app/app.php[33]: handle_error(4)
[2] file: /home/public/e-bible.app/app/index.php[12]: require_once(1)
[3] file: /home/public/e-bible.app/index.php[28]: require_once(1)
=== DEBUG ===