BhG 5.12

syntax

yuktaḥ (engaged) karma-phalam (the fruit of activity) tyaktvā (after abandoning),
naiṣṭhikīm (the final) śāntim (tranquility) āpnoti (he obtains).
[kiṁtu] (but) ayuktaḥ (non engaged) kāma-kāreṇa (by the power of desire) phale (to the fruit) saktaḥ (attached) nibadhyate (he is bound).

grammar

yuktaḥ	–	yukta (√yuj – to yoke, to join, to engage) PP 1n.1 m. – yoked, endowed with, engaged, suitable;
karma-phalam	–	karma-phala 2n.1 m.; TP: karmaṇāṁ phalam iti – the fruit of activity (from: √kṛ – to do, karman – activity and its result; √phal – to ripen; phala – fruit, result);
tyaktvā	–	√tyaj (to abandon, to give up) absol. – after abandoning;
śāntim	–	śānti 2n.1 f. – tranquility, peace, satisfaction, end, death (from: √śam – to calm, to put to an end, to destroy);
āpnoti	–	√āp (to obtain) Praes. P 1v.1 – he obtains, he achieves;
naiṣṭhikīm	–	naiṣṭhikī 2n.1 f. – finnal, fixed, the highest (from: niṣṭhā – steadiness, faith);
ayuktaḥ	–	a-yukta (√yuj – to yoke, to join, to engage) PP 1n.1 m. – not yoked, not endowed with, not engaged;
kāma-kāreṇa	–	kāma-kāra 3n.1 m.; TP: kāmasya kāreṇeti – by the power of desire (from: √kam –to wish, to love, to long for, kāma – desire, love, pleasure; √kṛ – to do, kāra – suffix: making, doer, power);
phale	–	phala 7n.1 n. – in the fruit, in result (from: √phal – to ripen);
saktaḥ	–	sakta (√sañj – to attach, to stick, to embrace) PP 1n.1 m. – attached;
nibadhyate	–	ni-√bandh (to bind, to fetter) Praes. pass. 1v.1 – he is bound;

textual variants

kāma-kāreṇa → kāma-cāreṇa / karma-kāreṇa (by the move of desire / by the power of action);
nibadhyate → nibādhyate (he is bound);

Śāṃkara

yasmāc ca—

yukta īśvarāya karmaṇi karomi na mama phalāya ity evaṃ samāhitaḥ san karma-phalaṃ tyaktvā parityajya śāntiṃ mokṣākhyām āpnoti naiṣṭhikīṃ niṣṭhāyāṃ bhavāṃ sattva-śuddhi-jñāna-prāpti-sarva-karma-saṃnyāsa-jñāna-niṣṭhā-krameṇeti vākya-śeṣaḥ | yas tu punar ayukto’samāhitaḥ kāma-kāreṇa | karaṇaṃ kāraḥ kāmasya kāraḥ kāma-kāraḥ | tena kāma-kāreṇa kāma-preritatayety arthaḥ | mama phalāya idaṃ karomi karma ity evaṃ phale sakto nibadhyate | atas tvaṃ yukto bhava ity arthaḥ

Rāmānuja

yuktaḥ ātmavyatiriktaphaleṣv acapalaḥ ātmaikapravaṇaḥ, karmaphalaṃ tyaktvā kevalam ātmaśuddhaye karmānuṣṭhāya naiṣṭhikīṃ śāntim āpnoti sthirām ātmānubhavarūpāṃ nirvṛtim āpnoti / ayuktaḥ ātmavyatiriktaphaleṣu capalaḥ ātmāvalokanavimukhaḥ kāmakāreṇa phale saktaḥ karmāṇi kurvan nityaṃ karmabhir badhyate nityasaṃsārī bhavati / ataḥ phalasaṅgarahitaḥ indriyākāreṇa pariṇatāyāṃ prakṛtau karmāṇi saṃnyasya ātmano bandhamocanāyaiva karmāṇi kurvītetyuktaṃ bhavati

Śrīdhara

nanu kathaṃ tenaiva karmaṇā kaścin mucyate kaścid badhyate iti vyavasthā ? ata āha yukta iti | yuktaḥ parameśvaraika-niṣṭhaḥ san karmaṇaḥ phalaṃ tyaktvā karmaṇi kurvann ātyantikīṃ śāntiṃ mokṣaṃ prāpnoti | ayuktas tu bahirmukhaḥ kāma-kāreṇa kāmataḥ pravṛttyā phala āsakto nitarāṃ bandhaṃ prāpnoti

Madhusūdana

kartṛtvābhimāna-sāmye ‚pi tenaiva karmaṇā kaścin mucyate kaścit tu badhyata iti vaiṣamye ko hetur iti tatrāha yukta iti | yukta īśvarāyaivaitāni karmāṇi na mama phalāyety evam abhiprāyavān karma-phalaṃ tyaktvā karmāṇi kurvan śāntim mokṣākhyām āpnoti naiṣṭhikīṃ sattva-śuddhi-nitya-vastu-viveka-saṃnyāsa-jñāna-niṣṭhā-krameṇa jātām iti yāvat | yas tu punar ayukta īśvarāyaivaitāni karmāṇi na mama phalāyety abhiprāya-śūnyaḥ sa kāma-kāreṇa kāmataḥ pravṛttyā mama phalāyaivedaṃ karma karomīti phale sakto nibadhyate karmabhir nitarāṃ saṃsāra-bandhaṃ prāpnoti | yasmād evaṃ tasmāt tvam api yuktaḥ san karmāṇi kurv iti vākya-śeṣaḥ

Viśvanātha

karma-karaṇe anāsakty-āsaktī eva mokṣa-bandha-hetū ity āha yukto yogī niṣkāma-karmītity arthaḥ | naiṣṭhikīm niṣṭhā-prāptāṃ śāntiṃ mokṣam ity arthaḥ | ayuktaḥ sa-kāma-karmīty arthaḥ | kāma-kāreṇa kāma-pravṛttyā

Baladeva

yukta ātmārpita-manāḥ karma-phalaṃ tyaktvā kurvann naiṣṭhikīm sthirāṃ śāntim ātmāvaloka-lakṣaṇām āpnoti | ayukta ātmānarpita-manāḥ karma-phale saktaḥ kāma-kāreṇa kāmataḥ karmaṇi pravṛttyā nibadhyate saṃsarati