Interpreting the expression krsnapingalah as Hari and Hara, Nilakantha says: "Some argue that the two epithets apply to Siva, either because he was originally red, but afterwards became black, or that his throat was black and the rest of his body red, or that his left side was black and his right was red, or that he was black in his aspect of Prakrti and red when viewed as Purusa that energises, the former; now this assumption- whereby words denoting (connoting) attributes are made to denote the objects and since they possess these qualities to represent them at least in part-is too far-fetched.
We said that the words Vilohita and Krsna primarily denoted Siva and Kesava; hence Nila Pingala that are synonymous with the above stand for Hari Hara. The two pairs denote only Hari Hara. So we think that the meaning of unascertained words can be got through the meaning of words already explained. Even if it were possible to put up some shadow of evidence by some far-fetched assumption, we need not arrive at our conclusion by a crooked way, when the road is plain before us. Again since the names of Siva and Visnu are used interchangeably, and since the one Being manifests himself as two, our interpretation is the more consistent."9
9.See Siva-sahasranama-stotra, with Sri Nilakantha's Commentary, translated by R. Anantakrishna Sastri (V. Ramaswamy Sastrulu & Sons, Madras, 1955), p.50.