金光明經文句記 2.237

2.237

初、直明種善義。體本覺心，名法性地。觀性始覺，名為種子。下種種久，其義可知。五善根者，於本法性生不動信、進、念、定、慧。五皆不動，名為五根。此根生者，相似位高，故名增長。

First, directly clarifying the meaning of planting goodness. The essence of the original awakening mind is called the ground of the Dharma-nature. Contemplating the nature with initial awakening is called the seed. Planted as seeds long ago, its meaning can be known. As for the 'five good roots', regarding the original Dharma-nature, one gives rise to immovable faith, diligence, mindfulness, concentration, and wisdom. Because all five are immovable, they are called the five roots. When these roots arise, one's position of resemblance is high, and so it is called 'increasing'.