12.18

समः शत्रौ च मित्रे च तथा मानापमानयोः ।
शीतोष्णसुखदुःखेषु समः सङ्गविवर्जितः ॥

samaḥ śatrau ca mitre ca tathā mānāpamānayoḥ
śītoṣṇasukhaduḥkheṣu samaḥ saṅgavivarjitaḥ

Kṛṣṇa (कृष्ण) continues, and the sentence does not finish here: naraḥ (नरः) in 12.19 is the man these words describe.

The verse

The same toward enemy and friend, and so also in honor and disgrace, the same in cold and heat, joy and sorrow, left free of clinging — that is the man 12.19 calls dear.

नेपालीमा

शत्रु र मित्रप्रति समान, मान र अपमानमा पनि त्यस्तै, शीत र तापमा, सुख र दुःखमा समान, आसक्तिबाट छुटाइएको, यही मानिसलाई पछिको वचनले प्रिय भन्छ।

Where it sits

The pairs keep arriving. 12.13 had sorrow and joy as one compound. Here friend and enemy, honor and disgrace, cold and heat, joy and sorrow, are the field in which he is samaḥ (समः).

Split: समः + शत्रौ + च + मित्रे + च + तथा + मान-अपमानयोः + शीत-उष्ण-सुख-दुःखेषु + समः + सङ्ग-विवर्जितः

samaḥ + śatrau + ca + mitre + ca + tathā + māna-apamānayoḥ + śīta-uṣṇa-sukha-duḥkheṣu + samaḥ + saṅga-vivarjitaḥ

Sanskrit, in depth

The words

देवनागरीWordGrammarSense
समःsamaḥnominative singularthe same. Even.
शत्रौśatraulocative singulartoward the enemy. In the enemy.
चcaindeclinableand.
मित्रेmitrelocative singulartoward the friend.
चcaindeclinableand.
तथाtathāindeclinableso also.
मान-अपमानयोःmāna-apamānayoḥlocative dualin honor and disgrace. The dual ending because there are two.
शीत-उष्ण-सुख-दुःखेषुśīta-uṣṇa-sukha-duḥkheṣulocative pluralin cold, heat, joy, and sorrow.
समःsamaḥnominative singularthe same.
सङ्ग-विवर्जितःsaṅga-vivarjitaḥnominative singularleft free of clinging. saṅga (सङ्ग) "clinging contact." vivarjita (विवर्जित) "excluded, left."

The phrases

samaḥ śatrau ca mitre ca (समः शत्रौ च मित्रे च) is the first pair. The same toward enemy and toward friend. Both nouns are locative singular. samaḥ (समः) is the person, not a property of the enemy.

tathā mānāpamānayoḥ (तथा मानापमानयोः) extends it. So also in honor and in disgrace. The ending --yoḥ (योः) is dual: two things, one case. मान + अपमान māna + apamāna is mānāpamāna (मानापमान).

śītoṣṇasukhaduḥkheṣu samaḥ saṅgavivarjitaḥ (शीतोष्णसुखदुःखेषु समः सङ्गविवर्जितः) is the wider field, and the last nominative. The same in cold and heat, joy and sorrow, and clinging has left him. Four items, so the case is locative plural --eṣu (एषु). शीत + उष्ण śīta + uṣṇa is śītoṣṇa (शीतोष्ण).

Sanskrit in this line

samaḥ (समः) takes the locative. The locative answers where, and toward whom, he is the same. śatrau (शत्रौ) and mitre (मित्रे) are singular. mānāpamānayoḥ (मानापमानयोः) is dual, because honor and disgrace are two. śītoṣṇasukhaduḥkheṣu (शीतोष्णसुखदुःखेषु) is plural, because the list has gone past two. The case is one. The number follows the count.

Say it back

The pairs, and the case they sit in. If śatrau (शत्रौ) and mitre (मित्रे) come out as nominatives, a second pair of men has walked into the verse.