BhG 3.16

syntax

he pārtha (O son of Pṛthā!),
iha (here) yaḥ (he who) evam (thus) pravartitam (which is set in motion) cakram (wheel) na anuvartayati (he does not cause it to move on),
saḥ (he) aghāyuḥ (sinner) indriyārāmaḥ (whose delight is in the senses) mogham (in vain) jīvati (he lives).

grammar

evam	–	av. – thus;
pravartitam	–	pravartita (pra-√vṛt  – to start to act, to surpass) caus. PP 2n.1 n. – which is set in motion;
cakram	–	cakra 2n.1 n. – wheel, cycle, discus (from: √car – to move or from: √kṛ – to do);
na	–	av. – not;
anuvartayati	–	anu-√vṛt (to follow, to obey) Praes. caus. P 1v.1 – he causes sth to move on;
iha	–	av. – here (often meaning: in this world);
yaḥ	–	yat sn. 1n.1 m. – he who;
aghāyuḥ	–	agha-āyuḥ 1n.1 m.; BV: yasyāyur agham asti saḥ – whose life is sinful (from: agha – evil, sin, suffering; āyuḥ – life, vitality, health);
indriyārāmaḥ	–	indriya-ārāma 1n.1 m.; BV: yasyārāma indriyeṣv asti saḥ – whose delight is in the senses (from: √ind – to be powerful, indriya – the senses; ā-√ram – to desist, to delight, ā-rāma – delight, pleasure);
mogham	–	av. – in vain, uselessly (from: mogha – vain, useless);
pārtha	–	pārtha 8n.1 m. – O son of Pṛthā (from: √pṛth – to extend, pṛthā – Kuntī, mother of the sons of Pāṇḍu);
saḥ	–	tat sn. 1n.1 m. – he;
jīvati	–	√jīv (to live) Praes P 1v.1 – he lives;

textual variants

cakraṁ → karma (activity);
nānuvartayatīha → nānuvartayate ha / nānuvartayatīca (indeed he does not support/ and he does not support);
aghāyuḥ → alpāyuḥ (whose life is short);
moghaṁ → mohaṁ (in bewilderment);

Śāṃkara

The key:
an excerpt from the commented verse
quotes from the scriptures
starting polemic

He who follows not here the wheel thus set in motion, who is of sinful life, indulging in senses, he lives in vain, O son of Pritha.		evaṃ pravartitaṃ cakraṃ nānuvartayatīha yaḥ | aghāyur indriyārāmo moghaṃ pārtha sa jīvati ||3.16||
He who ought to perform action, but who, indulging in sensual pleasures, does not follow the wheel of the world thus set revolving by Īśvara, on the basis of the Veda and sacrifices, he lives in vain.		evam ittham īśvareṇa veda-yajña-pūrvakaṃ jagac-cakraṃ pravartitaṃ nānuvartayatīha loke yaḥ karmaṇy adhikṛtaḥ sann aghāyur aghaṃ pāpam āyur jīvanaṃ yasya so ’ghāyuḥ pāpa-jīvana iti yāvat | indriyārāmaḥ indriyair ārāmaḥ āramaṇam ākrīḍā viṣayeṣu yasya sa indriyārāmo moghaṃ vṛthā he pārtha, sa jīvati |
The main drift, therefore, of this section (3.4-16) is that action should be performed by the ignorant man, for whom it is intended. In 3.4-8, it was taught that till he attains the qualification for Devotion to the knowledge of the Self, the man who knows not the Self and is therefore qualified (for action only) should resort to Devotion to action as a means of attaining Devotion to knowledge;		tasmād ajñenādhikṛtena kartavyam eva karmeti prakaraṇārthaḥ | prāg ātma-jñāna-niṣṭhā-yogyatā-prāptes tādarthyena karma-yogānuṣṭhānam adhikṛtenānātmajñena kartavyam evety etan na karmaṇām anārambhād (BhG 3.4) ity ata ārabhya śarīra-yātrāpi ca te na prasidhyed akarmaṇa (BhG 3.8) ity evam antena pratipādya,
and, further, there were incidentally propounded (in 3.9-16) many reasons why the man who knows not the Self and is (therefore) qualified for action should perform it. Mention, too, has been made of evils arising from a neglect of action.		yajñārthāt karmaṇo ’nyatra (BhG 3.9) ity ādinā moghaṃ pārtha sa jīvati (BhG 3.16) ity evam antenāpi granthena prāsaṅgikam adhikṛtasyānātmavidaḥ karmānuṣṭhāne bahu kāraṇam uktam | tad-akaraṇe ca doṣa-saṃkīrtanaṃ kṛtam ||3.16||

Rāmānuja

punar api lokadṛṣṭyā śāstradṛṣṭyā ca sarvasya yajñamūlatvaṃ darśayitvā yajñānuvartanasyāvaśyakāryatām ananuvartane doṣaṃ cāha

„annāt sarvāṇi bhūtāni bhavanti parjanyāc cānnasaṃbhavaḥ” iti sarvalokasākṣikam / yajñāt parjanyo bhavatīti ca śāstreṇāvagamyate, „agnau prāstāhutiḥ samyagādityam upatiṣṭhate / ādityāj jāyate vṛṣṭiḥ” ityādinā / yajñaś ca dravyārjanādikartṛvyāpārarūpakarmasamudbhavaḥ, karma ca brahmodbhavam / atra ca brahmaśabdanirdiṣṭaṃ prakṛtipariṇāmarūpaṃ śarīram / „tasmād etad brahma nāma rūpam annaṃ ca jāyate” iti hi brahmaśabdena prakṛtinirdiṣṭā / ihāpi „mama yonir mahad brahma” iti vakṣyate / ataḥ karma brahmodbhavam iti prakṛtipariṇāmarūpaśarīrodbhavaṃ karmetyuktaṃ bhavati / brahmākṣarasamudbhavam ity atrākṣaraśabdanirdiṣṭo jīvātmā, annapānādinā tṛptākṣarādhiṣṭhitaṃ śarīraṃ karmaṇe prabhavatīti karmasādhanabhūtaṃ śarīram akṣarasamudbhavam; tasmāt sarvagataṃ brahma sarvādhikārigataṃ śarīraṃ nityaṃ yajñe pratiṣṭhitaṃ yajñamūlam ityarthaḥ / evaṃ paramapuruṣeṇa pravartitam idaṃ cakram annād bhūtaśabdanirdiṣṭāni sajīvāni śarīrāṇi, paryjanyād annam, yajñāt parjanyaḥ, yajñaś ca kartṛvyāpārarūpāt karmaṇaḥ, karma ca sajīvāc charīrāt, sajīvaṃ śarīraṃ punar apy annād ity anyonyakāryakāraṇabhāvena cakravat parivartamānam iha sādhane vartamāno yaḥ karmayogādhikārī jñānayogādhikārī vā nānuvartayati na pravartayati, yajñaśiṣṭena dehadhāraṇam akurvan so ‚ghāyur bhavati / aghārambhāyaiva yasyāyuḥ, aghapariṇataṃ vā, ubhayarūpaṃ vā so ‚ghāyuḥ / ata evendriyārāmo bhavati, nātmārāmaḥ; indriyāṇy evāsyodyānāni bhavanti; ayajñaśiṣṭavardhitadehamanastvenodriktarajastamaskaḥ ātmāvalokanavimukhatayā viṣayabhogaikaratir bhavati / ato jñānayogādau yatamāno ‚pi niṣphalaprayatnatayā moghaṃ pārtha sa jīvati

Śrīdhara

yasmād evaṃ parameśvareṇaiva bhūtānāṃ puruṣārtha-siddhaye karmādi-cakraṃ pravartitaṃ tasmāt tad akurvato vṛthaiva jīvitam ity āha evam iti | parameśvara-vākya-bhūtād vedākhyād brahmaṇaḥ puruṣāṇāṃ karmaṇi pravṛttiḥ | tataḥ karma-niṣpattiḥ | tataḥ parjanyaḥ | tato ‚nnam | tato bhūtāni | bhūtānāṃ punas tathaiva karma-pravṛttir iti | evaṃ pravartitaṃ cakraṃ yo nānuvartayati nānutiṣṭhati so ‚ghāyuḥ | aghaṃ pāpa-rūpam āyur yasya saḥ | yata indriyair viṣayeṣv evāramati, na tu īśvarārādhanārthe karmaṇi | ato moghaṃ vyarthaṃ sa jīvati

Madhusūdana

bhavaty evaṃ tataḥ kiṃ phalitam ity āha evam iti | parameśvarāt sarvāvabhāsaka-nitya-nirdoṣa-vedāvirbhāvaḥ | tataḥ karma-parijñānaṃ tato ‚nuṣṭhānād dharmotpādaḥ | tataḥ parjanyas tato ‚nnaṃ tato bhūtāni punas tathaiva bhūtānāṃ karma-pravṛttir ity evaṃ parameśvareṇa pravartitaṃ cakraṃ sarva-jagan-nirvāhakaṃ yo nānuvartayati nānutiṣṭhati so ‚ghāyuḥ pāpa-jīvano moghaṃ vyartham eva jīvati he pārtha tasya jīvanān maraṇam eva varaṃ janmāntare dharmānuṣṭhāna-sambhavād ity arthaḥ | tathā ca śrutiḥ – atho ayaṃ vā ātmā sarveṣāṃ bhūtānāṃ lokaḥ sa yaj juhoti yad yajate tena devānāṃ loko ‚tha yad anubrūte tena ṛṣīṇām atha yat-pitṛbhyo nipṛṇāti yat prajām icchate tena pitṝṇām atha yan manuṣyān vāsayate yad ebhyo ‚śanaṃ dadāti tena manuṣyāṇām atha yat paśubhyas tṛṇodakaṃ vindati tena paśūnāṃ yad asya gṛheṣu śvāpadā vayāṃsyāpipīlikābhya upajīvanti tena teṣāṃ lokaḥ [BAU 1.4.16] iti |

brahma-vidaṃ vyāvartayati indriyārāma iti | yata indriyair viṣayeṣv āramati ataḥ karmādhikārī saṃs tad-akaraṇāt pāpam evācinvan vyartham eva jīvatīty abhiprāyaḥ

Viśvanātha

etad-anuṣṭhāne pratyavāyam āha evam iti | cakraṃ pūrva-paścād-bhāgena pravartitam | yajñān parjanyaḥ | parjanyād annam | annāt puruṣaḥ | puruṣāt punar yajñaḥ | yajñāt parjanya ity evaṃ cakraṃ yo nānuvartayati yajñānuṣṭhānena na parivartayati, sa aghāyuḥ pāpa-vyāptāyuḥ | ko narake na maṅkṣyatīti bhāvaḥ

Baladeva

yajñākaraṇe doṣam āhaivam iti | parasmād brahmaṇo vedāvirbhāvas tasmād brahma-pratibodhakāt yajñas tataḥ parjanyas tato ‚nnaṃ tato bhūtāni punas tathaiva bhūtānāṃ karma-pravṛttir ity evaṃ nikhila-jagan-nirvāhakaṃ pareśena prajāpatinā pravartitaṃ cakraṃ yo nānuvartayati sa janaḥ pareśa-vimukho ‚ghāyuḥ pāpa-jīvano moghaṃ vyartham eva jīvati | he pārtha yad asāv indriyair viṣayeṣv eva ramate na tu para-brahmābhimate yajñe tac-cheṣāśane ca