Incomparably superior to the Wheel-turning Noble King are the Four Great Heavenly Kings including Vaiśravaṇa, who are the great kings of the Four Continents. Indra is the lord of Trāyastriṃsá (the heaven of the 33 gods) while the King of Devils in the Sixth Heaven dwells on top of the realm of desire and controls the triple world. They acquired such good fortune by virtue of observing the ten good precepts to the highest degree and through giving the root of goodness equally to all without discrimination. The King of the Mahābrahman Heaven, who is the lord of the triple world, dwells on the summit of the world of form waited on by the King of Devils and Indra, and he controls the triple-thousand worlds. This is the merit received from having practiced not only the meditation to eliminate worldly passions but also the Four Infinite Virtues (of benevolence, compassion, giving joy, and selflessness).

Hōren-shō, Letter to Hōren, Writings of Nichiren Shōnin, Volume 6, Followers I, Page 46