Shatapatha Brahmana 3.4.2.3

3.4.2.3

tasmādu ha na svā ṛtīyeran | ya eṣām parastarāmiva bhavati sa enānanuvyavaiti te priyaṃ dviṣatāṃ kurvanti dviṣadbhyo radhyanti tasmānna 'rtīyerantsa yo haivaṃ vidvānna 'rtīyate 'priyaṃ dviṣatāṃ karoti na dvipadbhyo radhyati tasmānna 'rtīyeta

For this reason let not kinsmen fall out, for any (enemy) of theirs, be he ever so far away, steps in between them; they do what pleases their enemies and fall a prey to their enemies: therefore let them not fall out. For he who, knowing this, quarrels not, does what displeases his enemies and falls not a prey to his enemies: let him therefore not quarrel.