Māvoca pharusaṃ kañci,
vuttā paṭivadeyyu taṃ.
Dukkhā hi sārambhakathā,
paṭidaṇḍā phuseyyu taṃ.

Speak not harshly to anyone,
for those thus spoken to might retort.
Indeed, angry speech hurts,
and retaliation may overtake you.

Dhammapada 10.133
The Dhammapada: The Buddha’s Path of Wisdom, translated from Pāli by Acharya Buddharakkhita