yoga-sthaḥ kuru karmāṇi
sańgaḿ tyaktvā dhanañjaya
siddhy-asiddhyoḥ samo bhūtvā
samatvaḿ yoga ucyate

Translation of Bhagavad Gita 2.48

Perform your duty equipoised, O Arjuna, abandoning all attachment to success or failure. Such equanimity is called yoga.

Commentary by Sri A.C. Bhaktivedanta Swami Prabhupada of Gaudiya Sampradaya:

Krishna tells Arjuna that he should act in yoga. And what is that yoga? Yoga means to concentrate the mind upon the Supreme by controlling the ever-disturbing senses. And who is the Supreme? The Supreme is the Lord. And because He Himself is telling Arjuna to fight, Arjuna has nothing to do with the results of the fight. Gain or victory are Krishna’s concern; Arjuna is simply advised to act according to the dictation of Krishna. The following of Krishna’s dictation is real yoga, and this is practiced in the process called Krishna consciousness. By Krishna consciousness only can one give up the sense of proprietorship. One has to become the servant of Krishna, or the servant of the servant of Krishna. That is the right way to discharge duty in Krishna consciousness, which alone can help one to act in yoga.

Arjuna is a kshatriya, and as such he is participating in the varnashrama-dharma institution. It is said in the Vishnu Purana that in the varnashrama-dharma, the whole aim is to satisfy Vishnu. No one should satisfy himself, as is the rule in the material world, but one should satisfy Krishna. So unless one satisfies Krishna, one cannot correctly observe the principles of varnashrama-dharma. Indirectly, Arjuna was advised to act as Krishna told him.

Commentary by Sri Vishvanatha Chakravarthi Thakur of Gaudiya Sampradaya:

With this verse, Krishna starts teaching the subject of niskama karma. Acting in this way, seeing victory and defeat as equal, O Arjuna, you should perform your duty of fighting. This performance of niskama karma yoga transforms into jnana yoga. Jnana yoga should be understood from the previous and latter portions of the work.

Commentary by Sri Ramanuja of Sri Sampradaya:

2.48 Abandoning the attachment to kingdom, relatives etc., and established in Yoga, engage in war and such other activities. Perform these with equanimity as regards success and failure resulting from victory etc., which are inherent in them. This equanimity with regard to success and failure is called here by the term Yoga, in the expression ‘established in Yoga.’ Yoga is equanimity of mind which takes the form of evenness in success and failure. Sri Krsna explains why this is repeatedly said:

Commentary by Sri Sridhara Swami of Rudra Sampradaya:

The fundamental question which might be raised is what then is factually to be done? This is now being answered in this verse. Established in the science of yoga perform all activities. Yoga is the science of the individual consciousness attaining communion with the Ultimate Consciousness. Being established by this yoga perform actions relinquishing attachment, motivation for rewards and depend solely upon the mercy of the Supreme Lord in all one’s activities. Totally unconcerned about success or failure, attainment or non-attainment resultant surrender in righteousness all actions as an offering unto the Supreme Lord. This is the eternal path called yoga by the wise as it consists of fixed concentration of the mind.

Commentary by Sri Madhvacharya of Brahma Sampradaya:

The previous verse 47 is further clarified here. Yoga, equanimity is the methodology encouraged. Relinquishing desire and attachment to the rewards of actions while steadfastly remaining equipoised in either success or failure. This verily is what is meant by equanimity.

Now begins the summation.

The meaning of the word sangam is attachment. Attachment to what? The rewards of one’s fruitive actions.

Commentary by Sri Keshava Kashmiri of Kumara Sampradaya:

What should one do? Lord Krishna states here to remain balanced and equipoised. Discard the mentality of being attached. Be balanced in either victory or defeat and perform your duties. Karmani refers to duties the plural usage of duties indicates various obligatory and occasional duties; but the optional duty is not to be included among these as they are not required. Otherwise there would be contradiction between the former and the latter statements. Yoga is explained by Lord Krishna Himself as being in the state of equanimity.

Commentary by Sri Adi Shankaracharya of Advaita Sampradaya:

2.48 If action is not to be undertaken by one who is under the impulsion of the fruits of action, how then are they to be undertaken? This is being stated: Yogasthah, by becoming established in Yoga; O Dhanajaya, kuru, undertake; karmani, actions, for the sake of God alone; even there, tyaktva, casting off; sangam, attachment, in the form, ‘God will be pleased with me.’ [‘Undertake work for pleasing God, but not for propitiating Him to become favourable towards yourself.’] Undertake actions bhutva, remaining; samah, equipoised; siddhi-asidhyoh, in success and failure — even in the success characterized by the attainment of Knowledge that arises from the purification of the mind when one performs actions without hankering for the results, and in the failure that arises from its opposite. [Ignorance, arising from the impurity of the mind.] What is that Yoga with regard to being established in which it is said, ‘undertake’? This indeed is that: the samatvam, equanimity in success and failure; ucyate, is called; yogah, Yoga.

Commentary by Sri Abhinavagupta of Kaula Tantra Sampradaya:

2.48 Yogasthah etc. Being established in Yoga you must perform actions. Evenness [of mind] is the Yoga.

Sanskrit Shloka Without Transliteration Marks:

yoga-sthah kuru karmani
sangam tyaktva dhananjaya
siddhy-asiddhyoh samo bhutva
samatvam yoga ucyate

Sanskrit to English Word for Word Meanings:

yoga-sthaḥ — equipoised; kuru — perform; karmāṇi — your duties; sańgam — attachment; tyaktvā — giving up; dhanañjaya — O Arjuna; siddhi-asiddhyoḥ — in success and failure; samaḥ — equipoised; bhūtvā — becoming; samatvam — equanimity; yogaḥ — yoga; ucyate — is called.