śrī-bhagavān uvāca
kāma ea krodha ea
rajo-gua-samudbhava
mahāśano mahā-pāpmā
viddhy enam iha vairiam

Translation of Bhagavad Gita 3.37

The Supreme Personality of Godhead said: It is lust only, Arjuna, which is born of contact with the material mode of passion and later transformed into wrath, and which is the all-devouring sinful enemy of this world.

Commentary by Sri Vishvanatha Chakravarthi Thakur of Gaudiya Sampradaya:

Lust, composed of the desire of the sense objects, impels a man to sin. A man, being urged by lust, engages in sin. This lust, appearing in a different form, becomes visible as anger. This means that lust, being obstructed by someone, transforms into anger. Lust arises from the mode of passion, and from lust in mode of passion arises anger in the mode of ignorance.

“But after the fulfillment of desire, the desire should be finished.”

“No, this lust is a great devourer. It is impossible to satisfy the expectations of desire.”

As the smrti says,

yat prthivyam vrihi-yavarm hiranyam pasavah striyah
nalam ekasya tat sarvam iti matva samam vrajet

Understanding that all that is available on earth in the form of food, gold, animals and women is not enough for one person, one should go about with peaceful mind. Mahabharata, Anusasana Parva, Ch.13

“If it is not possible to make an alliance with lust by giving (dana), then is it possible to bring under control by sama and bheda?”

“No, lust is a very great demon (maha papma).”

Commentary by Sri Ramanuja of Sri Sampradaya:

3.37 The Lord said — The highly ravenous desire is born of the Guna Rajas originating from old subtle impressions. It has for its objects sound and other sense contacts. It is a foe to him who is practising Jnana Yoga, as he is joined with Prakrti constituted of the Gunas which rise and subside periodically. It attracts him towards the objects of the senses. It is this desire alone which, when hampered, develops into anger towards those persons who are the cause of such hindrance. It is a powerful cause of sin. It incites the aspirant to do harm to others. Know this, which is born of the Guna called Rajas, as the natural enemy of Jnana Yogins.

Commentary by Sri Sridhara Swami of Rudra Sampradaya:

The answer to Arjuna’s previous question is now being answered by Lord Krishna. The main cause for such flagrant behaviour is kama or lust. Also krodha or anger is spoken about but it is actually instigated by lust as well. This is because when kama is unable to satisfy its desires then immediately it takes the form of krodha. This kama is born from rajas guna or the mode of passion. This indicates that when there is an increase of sattva guna or the mode of goodness then kama will be decreased proportionately. It should be clearly understood that kama and krodha are formidable enemies on the path of moksa or liberation from the cycle of birth and death. Both kama and krodha must be terminated by the method Lord Krishna prescribes in the next verses; for it is definitely not appropriate to try to appease either of them as it is useless to try to pacify kama because it has an insatiable appetite and is never satisfied and it is also useless to appease krodha because it is has a terribly temperament and is unpredictably sinful.

Commentary by Sri Madhvacharya of Brahma Sampradaya:

The influence which is the most powerful and destructive on human beings is kama or lust followed by krodha or anger which arises from frustrated desires. Those who hypothesise contrarily are not cognisant of the subtle difference involved in the mixture of the two. Therefore it can be understood that without desire there is no opportunity for anger to manifest and indeed it does not. Since there are many causes of anger it is called mahashanah or great devourer. Since anger becomes the cause of committing abominable actions it is called mahapaapma or great sinner and because it is counter productive to all human goals of righteousness it is called mahavairi or great adversary.

Commentary by Sri Keshava Kashmiri of Kumara Sampradaya:

Lord Krishna is explicitly confirming that the root cause and great impeller of sins is kama or lust known to forcefully compel one’s senses to race impetuously towards objects of the senses. But kama’s subordinate krodha or anger is also the cause of many evils like violence. When lust is impeded and desires are frustrated it is anger that replaces lust in another form. Hence krodha is also a form of kama and both arise out of rajas guna or the mode of passion. This suggests that by increasing sattva guna or the mode of goodnes the effects of rajas guna can be decreased and subsequently the power of desires is less. Because controlling desires one controls lust and controlling lust one controls anger. There is no other way. Thus one should not miss that they are inteconnected and try to control each seperately. But kama is extremely difficult to control once it has been activated because it is insatiable and it does not become tranquil after even enjoying wealth, pleasure of the flesh, kingdoms and even the whole world; to the contrary its desires increases exactly as a fire increases when oil is poured on it, it rages out of control and so it is an extremely evil propensity and when impeded it explodes into anger destroying all in its path like a horrific forest fire.

Commentary by Sri Adi Shankaracharya of Advaita Sampradaya:

3.37 Esah, this; kamah, desire, is the enemy of the whole world, because of which the creatures incur all evil. This desire when obstructed in any way turns into anger. Therefore, krodhah, anger, is also identical with this (desire). It is rajoguna-samudbhavah, born of the quality of rajas; or, it is the origin of the quality of rajas. For, when desire comes into being, it instigates a person by arousing rajas. People who are engaged in service etc., which are effects of rajas, and who are stricken with sorrow are heard to lament, ‘I have been led to act by desire indeed!’ It is mahaasanah, a great devourer, whose food is enormous. And hence, indeed, it is maha-papma, a great sinner. For a being commits sin when goaded by desire. Therefore, viddhi, know; enam, this desire; to be vairinam, the enemy; iha, here in this world. With the help of examples the Lord explains how it is an enemy:

Commentary by Sri Abhinavagupta of Kaula Tantra Sampradaya:

3.37 Kama esah etc. A total absence of difference among these two (desire and wrath) is indicated by the word esah ‘this’ twice uttered. These desire and wrath are ever interrelated and remain in an inseparable mutual co-existence. Hence [the Lord] well describes them only as identical. This is a swallower i.e., a devouer of the morsel of festival i.e., the happiness. The wrath alone is a bestower of sins as it is the cause of great sins. This is man of intelligence should view to be an enemy.

Sanskrit Shloka Without Transliteration Marks:

sri-bhagavan uvaca
kama esa krodha esa
rajo-guna-samudbhavah
mahasano maha-papma
viddhy enam iha vairinam

Sanskrit to English Word for Word Meanings:

śri-bhagavān uvāca — the Personality of Godhead said; kāmaḥ — lust; eṣaḥ — this; krodhaḥ — wrath; eṣaḥ — this; rajaḥ-guṇa — the mode of passion; samudbhavaḥ — born of; mahā-aśanaḥ — all-devouring; mahā-pāpmā — greatly sinful; viddhi — know; enam — this; iha — in the material world; vairiṇam — greatest enemy.