He who knowing this sings a Sâman, sings to both (the adhidaivata and adhyâtma self, the person in the sun and the person in the eye, as one and the same person). He obtains through the one, yea, he obtains the worlds beyond that, and the wishes of the Devas;

In plain words: A person who understands this and sings the chant is praising both at once: the divine person in the sun and the one in the eye, as one being. Through the one in the sun, he gains the higher worlds and what the gods wish for.