ཕྱི་ནང་སྟོང་པ་ཉིད་ནི་ཕྱི་ནང་སྟོང་པ་ཉིད་ཀྱིས་སྟོང་སྟེ།
If you ask why, it is because these two, the emptiness of external and internal phenomena and the perfections, are without duality and cannot be divided into two.
Emptiness, Perishing, Non-duality