BhG 8.25

syntax

dhūmaḥ (smoke) rātriḥ (night) tatha kṛṣṇaḥ (also dark [fortnight]) ṣaṇ-māsāḥ dakṣiṇāyanam (six months of the southern path),
tatra (here) yogī (a yogī) cāndramasam jyotiḥ (light of the Moon) prāpya (after obtaining) nivartate (he returns).

grammar

dhūmaḥ	–	dhūma 1n.1 m. – smoke (from: √dhū – to shake, to kindle);
rātriḥ	–	rātri 1n.1 f. – night (from: √rā – to grant or √ram – to play, to rejoice);
tathā	–	av. – in that manner, so, in like manner;
kṛṣṇaḥ	–	kṛṣṇa 1n.1 m. – black, dark, dark fortnight (kṛṣṇa-pakṣa – half the month when the Moon wanes);
ṣaṇ-māsāḥ	–	ṣaṇ-māsa 1n.3 m. – six months (from: ṣaṭ / ṣaṣ – six; mās – Moon, month, māsa – month);
dakṣiṇāyanam	–	dakṣiṇa-ayaṇa 1n.1 n. – the southern path [of the Sun], from summer to winter solstice (from: dakṣiṇa – right, southern, gift, walking round as a sign of respect; ayana – a path, course);
tatra	–	av. – there (from: tat; indeclinable locative with an ending -tra);
cāndramasam	–	cāndra-masa 1n.1 n. – pertaining to the Moon (from: candramas – Moon);
jyotiḥ	–	jyotiḥ 1n.1 n. – light, brightness, fire, eye;
yogī	–	yogin 1n.1 m. – a yogī, engaged (√yuj – to yoke, to join, to engage, yoga – yoga, yoking, application, a means, one of the schools of Hindu philosophy);
prāpya	–	pra-√āp (to obtain) absol. – after obtaining;
nivartate	–	ni-√vṛt (to stop, to turn back) Praes. Ā 1v.1 – he returns;

textual variants

kṛṣṇaḥ → kṛṣṇā (dark);
dhūmo rātris tathā kṛṣṇaḥ → dhūmaḥ kṛṣṇas tathā rātriḥ (smoke, dark fortnight, also night);
nivartate → na muhyati (he does not get bewildered);

Śāṃkara

dhūmo rātrir dhūmābhimāninī rātry-abhimāninī ca devatā | tathā kṛṣṇaḥ kṛṣṇa-pakṣa-devatā | ṣaṇ-māsā dakṣiṇāyanam iti ca pūrvavat devataiva | tatra candramasi bhavaṃ cāndramasaṃ jyotiḥ phalam iṣṭādi-kārī yogī karmī prāpya bhuktvā tat-kṣayād iha punar nivartate

Rāmānuja

etac ca dhūmādimārgasthapitṛlokādeḥ pradarśanam / atra yogiśabdaḥ puṇyakarmasaṃbandhiviṣayaḥ

Śrīdhara

āvṛtti-mārgam āha dhūma iti | dhūmo dhūmābhimāninī devatā | rātry-ādi-śabdaiś ca pūrvavad eva rātri-kṛṣṇa-pakṣa-dakṣiṇāyana-rūpa-ṣaṇ-māsābhimāninyas tisro devatā upalakṣyante | etābhir devatābhir upalakṣito yo mārgas tatra prayātaḥ karma-yogī cāndramasaṃ jyotis tad-upalakṣitaṃ svarga-lokaṃ prāpya tatreṣṭāpūrta-karma-phalaṃ bhuktvā punar āvartate | tatrāpi śrutiḥ-te dhūmam abhi sambhavanti dhūmād rātriṃ rātrer apakṣīyamāṇa-pakṣam apakṣīyamāṇa-pakṣād yān ṣaṇmāsān dakṣiṇāditya eti māsebhyaḥ pitṛ-lokaṃ pitṛ-lokāt candraṃ te candraṃ prāpya annaṃ bhavanti iti | tad evaṃ nivṛtti-karma-sahitopāsanayā krama-muktiḥ kāmya-karmabhiś ca svarga-bhogānantaram āvṛttiḥ | niṣiddha-karmabhis tu naraka-bhogānāntaram āvṛttiḥ | kṣudra-karmaṇāṃ tu jantūnām atraiva punaḥ punar janmeti draṣṭavyam

Madhusūdana

deva-yāna-mārgastuty-arthaṃ pitṛ-yāna-mārgam āha dhūma iti | atrāpi dhūma iti dhūmābhimāninī devatā rātrir iti rātry-abhimāninī kṛṣṇa iti kṛṣṇa-pakṣābhimāninī | ṣaṇmāsā dakṣiṇāyanam iti dakṣiṇāyanābhimāninī lakṣyate etad apy anyāsāṃ śruty-uktānām upalakṣaṇam | tathā hi śrutiḥ — te dhūmam abhi sambhavanti dhūmād rātriṃ rātrer apara-pakṣam apara-kṣīyamāṇa-pakṣād yān ṣaḍ-dakṣiṇaiti māsāṃs tān anite saṃvatsaram abhiprāpnuvanti māsebhyaḥ pitṛ-lokaṃ pitṛ-lokād ākāśam ākāśāc candramasam eṣa somo rājā tad-devānām annaṃ taṃ devā bhakṣayanti tasmin yāvat saṃpātam uṣitvāthaitam evādhvyānaṃ punar nivartante iti | tatra tasmin pathi prayātāś cāndramasaṃ jyotiḥ phalaṃ yogī karma-yogīṣṭāpūrta-datta-kārī prāpya yāvat-sampātam uṣitvā nivartate | sampataty aneneti sampātaḥ karma | tasmād etasmād āvṛtti-mārgād anāvṛtti-mārgaḥ śreyān ity arthaḥ

Viśvanātha

karmiṇām āvṛtti-mārgam āha dhūma iti | dhūmābhimāninī devatā | rātry-ādi-śabdaiś ca pūrvavad eva tat-tad-abhimāninyas tisro devatā lakṣyante | etābhir devatābhir upalakṣito yo mārgas tatra prayātaḥ karma-yogī cāndramasaṃ jyotis tad-upalakṣitaṃ svarga-lokaṃ prāpya karma-phalaṃ bhuktvā nivartate

Baladeva

athāvṛtti-patham āha dhūmo rātrir iti | tatrāpi pūrvavat dhūma-rātri-kṛṣṇa-pakṣa-ṣaṇmāsātmaka-dakṣiṇāyanānām abhimānino devā lakṣyāḥ | saṃvatsara-pitṛ-lokākāśa-candramasāṃ śruty-uktānām upalakṣaṇam etat | chāndogyāḥ paṭhanti – atha ya ime grāma iṣṭā-pūrte dattam ity upāsate te dhūmam abhisambhavanti | dhūmād rātriṃ rātrer apara-pakṣam apara-pakṣādyān ṣaḍ-dakṣiṇaiti māsāṃs tān naite saṃvatsaram abhiprāpnuvanti || māsebhyaḥ pitṛ-lokaṃ pitṛ-lokād ākāśam ākāśāc candramasam eṣa somo rājā tad devānām annaṃ taṃ devā bhakṣayanti | tasmin yavāt saṃpātam uṣitvāthaitam evādhvānaṃ punar nivartante (5.10.3-5) iti |

tathā ca dhūmādibhiḥ pareśa-nideśasthair aṣṭabhir devaiḥ pālitena pathā kāmya-karmiṇaś candra-lokaṃ pāpya bhoga-kṣaye sati tasmāt punar nivartanta iti