Chapter XVII · Śloka 15
Śrī Kṛṣṇa uvāca
अनुद्वेगकरं वाक्यं सत्यं प्रियहितं च यत् |
स्वाध्यायाभ्यसनं चैव वाङ्मयं तप उच्यते ||
स्वाध्यायाभ्यसनं चैव वाङ्मयं तप उच्यते ||
anudvega-karaṃ vākyaṃ satyaṃ priya-hitaṃ ca yat |
svādhyāyābhyasanaṃ caiva vāṅ-mayaṃ tapa ucyate ||
svādhyāyābhyasanaṃ caiva vāṅ-mayaṃ tapa ucyate ||
Speech that causes no agitation, that is truthful, pleasing, and beneficial — and also the practice of scriptural recitation — these are called the austerity of speech.
The tapas of speech operates on four axes at once: non-disturbance, truth, kindness, and benefit. When all four are met, speech becomes a spiritual discipline. To speak only what is true, necessary, gentle, and helpful is demanding — more so than most physical austerities.