Cattāri Brahmavihārā

Māvoca pharusaṃ kañci,vuttā paṭivadeyyu taṃ.

Dukkhā hi sārambhakathā,

paṭidaṇḍā phuseyyu taṃ.

Listen: http://host.pariyatti.org/dwob/dhammapada_10_133.mp3
Speak not harshly to anyone,

for those thus spoken to might retort.

Indeed, angry speech hurts,

and retaliation may overtake you.

Dhammapada 10.133

http://tipitaka.org/romn/cscd/s0502m.mul9.xml#para133

The Dhammapada: The Buddha’s Path of Wisdom, translated from the Pali by Acharya Buddharakkhita