Shatapatha Brahmana 14.3.1.27

14.3.1.27

atha cātvāle mārjayante sumitriyā na āpa oṣadhayaḥ santvityañjalināpa upācati vajro vā āpo vajreṇaivaitanmitradheyaṃ kurute durmitriyāstasmai santu yo'smāndveṣṭi yaṃ ca vayaṃ dviṣma iti yāmasya diśaṃ dveṣyaḥ syāttāṃ diśaṃ parāsiñcettenaiva tam parābhāvayati

They then cleanse themselves at the pit. With (Vâg. S. XXXVIII, 23), 'May the waters and plants be friendly unto us,' he takes water in his joined hands; for water is a thunderbolt: he thus makes a covenant with the thunderbolt;--and with, 'May they be unfriendly unto him who hateth us, and whom we hate!' let him sprinkle it in whatever direction he who is hateful to him may be, and he thereby overthrows him.