I have written out and sent to you an explanation of “the Buddha of the twelve kinds of light,” which people are speaking of. It was not possible to write in detail. I have set it forth only roughly.
In brief, you should take that which is called Buddha of unhindered light as fundamental. You should understand that Buddha of unhindered light is spoken of thus in order to indicate that [this Buddha] seeks to save all beings, unhindered by their being wretched and evil.
Respectfully.
Tenth month, 21st day
Shinran
Reply to Yuishin-bo