The System of the Vedanta according to Badarayana's Brahma-Sutras and Cankara's Commentary c8.s7.t2.5.2

c8.s7.t2.5.2

From the uniformity of case it does not follow that all (each for itself) fulfil the same purpose; they may fulfil different ends which require to be combined (p. 791, 7) and as a man can be at home and in bed at the same time, the soul too can be simultaneously in the veins, the pericardium, and the Brahman (p. 791, 8). Where (as in Chānd. 8, 6, 3) the veins alone are mentioned, without excluding Brahman who dwells, as we know, in another spot [in the ether of the heart], an entrance into Brahman by means of the veins (nāḍī-dvāreṇa) is to be understood (p. 791, 16); this is not in contradiction with the locative; for he who by means of the Ganges (Gaṅgayā) journeys to the ocean, has journeyed on the Ganges (Gaṅgāyām) (p. 792, 1). Moreover the passage in question is concerned with another matter, viz. the way through the veins and sunbeams into the Brahman-world [in heaven]; and in treating of this it is, to exalt the veins, mentioned that no evil touches him who has entered by them [into the heart], and that because, as Chānd. 6, 8, 3 says, "he has thus become one with heat" (p. 792, 5). By heat (tejas) is here to be understood either the juice (pittam) in the veins that surrounds the organs of cognition (p. 792, 6) or Brahman; for (p. 792, 11) that it cannot be touched by evil agrees with the facts of the Brahman-world [in the heart, cf. above p. 164] while the complex of veins issues (anugata) in Brahman, as the place of deep sleep.