Bhagavad Gita Ch. 18 “Yoga of Liberation through Renunciation” Verses  36, 37, 38 & 39
Lecture discusses three types of Sukha - Happiness.  Satvika – Sukha feels like poison in the beginning but in the end it feels like nectar.  Rajasika – Sukha feels like nectar in the beginning but in the end it feels like poison Tamasika – Sukha  feels like poison in the beginning and in the end also it feels like poison.
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