yat tad agre ’mṛtopamam
pariṇāme viṣam iva
tat sukhaḿ rājasaḿ smṛtam

Translation of Bhagavad Gita 18.38

That happiness which is derived from contact of the senses with their objects and which appears like nectar at first but poison at the end is said to be of the nature of passion.

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

A young man and a young woman meet, and the senses drive the young man to see her, to touch her and to have sexual intercourse. In the beginning this may be very pleasing to the senses, but at the end, or after some time, it becomes just like poison. They are separated or there is divorce, there is lamentation, there is sorrow, etc. Such happiness is always in the mode of passion. Happiness derived from a combination of the senses and the sense objects is always a cause of distress and should be avoided by all means.

Commentary by Sri Vishvanatha Chakravarthi Thakur of Gaudiya Sampradaya:

Rajasika happiness is like nectar in the beginning, as in the case of enjoying sex with others’ wives.

Commentary by Sri Ramanuja of Sri Sampradaya:

18.38 That which at the ‘beginning,’ i.e., at the time of experience looks like elixir because of the contact of senses with their objects agreable to them, but ‘at the end,’ i.e., when satiation or further incapacity to enjoy due to over-indulgence in them occurs, looks life poison — that pleasure is said to be Rajasika. In this latter state these so-called enjoyments cause the misery of Naraka.

Commentary by Sri Sridhara Swami of Rudra Sampradaya:

The sukham or happiness that arises innately due to the interaction of the five senses: eyes, ears, noses, tongue and body with the objects of the senses, which seems just like nectar in the beginning but after constant repetition over and over again unlimitedly becomes like poison in the end causing pain and discomfort in the present life and the next life Lord Krishna declares is situated in raja guna the mode of passion.

Commentary by Sri Madhvacharya of Brahma Sampradaya:

Sri Madhvacharya did not comment on this sloka.

Commentary by Sri Keshava Kashmiri of Kumara Sampradaya:

The sukham or happiness that is derived from sense gratification by the contact with the objects of the senses such as sexual and sensual bodily enjoyments, although seeming to be like nectar in the beginning when it is fresh and newly experienced but later after habitual repetition over and over again continuously throughout one’s life it becomes just like venom yielding unhappiness in this world and the next. Such activities are for begetting children in the grihasta ashram or married life and perpetuating the species otherwisw such activites keep on in bondage and and hence are deplorable. Such sukham Lord Krishna confirms as situated in raja guna the mode of passion.

Commentary by Sri Adi Shankaracharya of Advaita Sampradaya:

18.38 Tat, that; sukham, joy; is smrtam, referred to; as rajasam, born of rajas; yat, which; visaya-indriya-samyogat, arising from the contact of the organs and (their) objects; is amrtopamam, like nectar; agre, in the beginning, in the intial moments; but iva, like; visam, poison; pariname, at the end-at the end of full enjoyment of the objects (of the senses), because it causes loss of strength, vigour, beauty, wisdom, [Prajna, the capacity to understand whatever is heard.] retentive faculty, wealth and diligence, and because it is the cause of vice and its consequent hell etc.

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 ’mrtopamam
pariname visam iva
tat sukham rajasam smrtam

Sanskrit to English Word for Word Meanings:

viṣaya — of the objects of the senses; indriya — and the senses; saḿyogāt — from the combination; yat — which; tat — that; agre — in the beginning; amṛta-upamam — just like nectar; pariṇāme — at the end; viṣam iva — like poison; tat — that; sukham — happiness; rājasam — in the mode of passion; smṛtam — is considered.