Śatapatha Brāhmaṇa ("of a hundred paths") 1.3.4.8

1.3.4.8

athābhyādhāya japati | sūryastvā purastātpātu kasyāścidabhiśastyā iti guptyai vā abhitaḥ paridhayo bhavantyathaitatsūryameva purastādgoptāraṃ karoti netpurastānnāṣṭrā rakṣām\syabhyavacarāniti sūryo hi nāṣṭrāṇāṃ rakṣasāmapahantā

When he has put it on, he murmurs (ib.), 'May the sun guard thee from the east against any imprecation!' for the enclosing-sticks serve for protection on all (the other three) sides; and thereby he makes the sun the protector on the east side, fearing 'lest the evil spirits, the Rakshas, should rush in from the east:' for the sun is the repeller of the evil spirits, the Rakshas.