Chapter 17 · The Three Kinds of Faith · Krishna said
Bhagavad Gita 17.15 — Austerity of speech
अनुद्वेगकरं वाक्यं सत्यं प्रियहितं च यत्। स्वाध्यायाभ्यसनं चैव वाङ्मयं तप उच्यते ॥
anudvegakaraṃ vākyaṃ satyaṃ priyahitaṃ ca yat | svādhyāyābhyasanaṃ caiva vāṅmayaṃ tapa ucyate ||
Meaning
Words that cause no hurt, that are true, kind and helpful, along with regular reading and recitation of scripture — this is called austerity of speech.
In today's life
Before you speak, check three things — is it true, is it kind, and will it help?