yat tad agre viṣam iva
pariṇāme ’mṛtopamam
tat sukhaḿ sāttvikaḿ proktam

Translation of Bhagavad Gita 18.37

That which in the beginning may be just like poison but at the end is just like nectar and which awakens one to self-realization is said to be happiness in the mode of goodness.

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

In the pursuit of self-realization, one has to follow many rules and regulations to control the mind and the senses and to concentrate the mind on the self. All these procedures are very difficult, bitter like poison, but if one is successful in following the regulations and comes to the transcendental position, he begins to drink real nectar, and he enjoys life.

Commentary by Sri Vishvanatha Chakravarthi Thakur of Gaudiya Sampradaya:

(Combined commentary for verses 36 and 37)

Now sattvika happiness is described in one and a half verses.

Only by constant practice (abhyasat), does such a person enjoy. This means that is not like happiness derived from sense objects, which gives pleasure just on contact.

Enjoying in that happiness, the person crosses over the suffering of samsara (duhkhantam nigacchati). In the beginning, sattvika happiness is like poison, since restraining the senses and mind causes suffering.

Commentary by Sri Ramanuja of Sri Sampradaya:

18.37 That pleasure, which ‘at the beginning,’ i.e., at the time of beginning of Yoga, is ‘like poison,’ i.e., is painful because it requires strenuous efforts and because the distinct nature of the self is not yet experienced, but which after long practice fructifies in the blissful experience of the self — that joy born of a serene state of mind ‘focusing on the self’ is Sattvika. The Buddhi concerning the self is ‘Atama-buddhi.’ When all objects are withdrawn from that Buddhi it becomes serene (Prasanna). The joy born of the experience of the self in its distinct nature, when all objects are withdrawn from the Buddhi, becomes ‘like elixir’. That joy is said to be Sattvika.

Commentary by Sri Sridhara Swami of Rudra Sampradaya:

The threefold expressions of sukham or happiness influenced by the three gunas or modes of material nature are now explained by Lord Krishna beginning with sattva guna the mode of goodness. The happiness which is not sudden and direct like sense gratification but is tempered and disciplined due to relishing affection by its devotion and practice by which one rejoices when arriving at the state of cessation of all pain and misery. This happiness which appears in the beginning to be difficult and painful like poison due to establishing its independence from the mundane mind and senses; but in the end it is amrta-upamam just like nectar. Such consciousness is atma-buddhi of the nature of the soul and is serene and sublime. Having relinquished and abandoned the impurities of raja guna the mode of passion and tama guna the mode of ignorance such sukham becomes pristine and pure. This sukham is invariably situated in sattva guna.

Commentary by Sri Madhvacharya of Brahma Sampradaya:

Sri Madhvacharya did not comment on this sloka.

Commentary by Sri Keshava Kashmiri of Kumara Sampradaya:

Thus after presenting how the three gunas or modes of material nature influence knowledge, action, agent, intellect and determination; Lord Krishna elaborates upon the three types of sukham or happiness aspired for by every human being because all of the aforementioned factors are enacted for the sake of receiving happiness. Now the three forms of sukham will be explained to reveal what is to be embraced and what is to be avoided. The sukham by which one experiences unabated pleasure by consistent practice of devotion, meditation and adoration of the Supreme Lord Krishna or any of His authorised incarnations as revealed in Vedic scriptures is situated in sattva guna the mode of goodness. Such sukham is unhampered by the pangs of sense gratification and the attraction for sense objects and its temporary illusions of pleasure. Hence that which in the beginning by practice of detachment, restraint, renunciation, austerities, meditation, etc. appear to be like poison but at the end when they have been perfected are just like nectar, extremely delicious. By meditation on the Supreme Lord Krishna and constantly focused internally on the atma r immortal soul one stays established in sattva guna. The serenity and equanimity one derives from such sukham is like an elixir to the purified mind arising from abandonment of desire and cessation of passion, greed and infatuation that are the by products of raja guna the mode of passion and tama guna the mode of ignorance.

Commentary by Sri Adi Shankaracharya of Advaita Sampradaya:

18.37 Yat, that joy which is; iva, like; visam, poison, a source of pain; agre, in the beginning-when it first comes in the early stages of (acquisition) of knowledge, detachment, meditation and absorption, since they involve great struggle; but amrtopamam, comparable to nectar; pariname, in the end, when it arises from the maturity of knowledge, detachment, etc.; and which atma-buddhi-prasadajam, arises from the purity (prasada), trasparence like water, of one’s intellect (atma-buddhi); tat, that; sukham, joy; is proktam, spoken of, by the learned ones ;as sattvikam, born of sattva. Or, the phrase atma-buddhi-prasadajam may mean ‘arising from the high degree of clearness of that atma-buddhi (knowledge of or connected with the Self)’; therefore it is born of sattva.

Commentary by Sri Abhinavagupta of Kaula Tantra Sampradaya:

18.36-39 Sukham etc. upto udahrtam. At its time : at the time of its practice (use). Like poison (1st) : Because it is extremely difficult to give up the attachment for sense-objects cultivated during hundreds of [previous] life-periods. That has been said in the revealed literature as : ‘[The path of sprituality] is the edge of a razor, painful and difficult to cross over etc.’ The serenity of intellect (or mind) results from serenity in the Self, as there exists nothing else to be aspired for. The [Rajasic] happiness springs from the mutual contact between the sense-objects and senses, just as in the case of the eye due to its contact with colur. That happiness which is due to sleep, indolence and heedlessness, explained earlier, is of the Tamas (Strand).

Sanskrit Shloka Without Transliteration Marks:

yat tad agre visam iva
pariname ’mrtopamam
tat sukham sattvikam proktam

Sanskrit to English Word for Word Meanings:

yat — which; tat — that; agre — in the beginning; viṣam iva — like poison; pariṇāme — at the end; amṛta — nectar; upamam — compared to; tat — that; sukham — happiness; sāttvikam — in the mode of goodness; proktam — is said; ātma — in the self; buddhi — of intelligence; prasāda-jam — born of the satisfaction.