Bhagavad Gita Chapter 18 Verse 39
यत्, अग्रे, च, अनुबन्धे, च, सुखम् मोहनम्, आत्मनः,
निद्रालस्यप्रमादोत्थम्, तत्, तामसम्, उदाहृतम्।।39।।
Yat’, agre, ch, anubandhe, ch, sukham’, mohnam’, aatmanH,
Nidraalasyaprmaadottham’, tat’, taamsam’, udaahrtam’ ||39||
Translation: (Yat’) which (sukham’) happiness (ch) and (agre) at first at the time of experience (ch) and (anubandhe) in the end (aatmanH) soul (mohnam’) deludes (tat’) that (nidraalasyaprmaadottham’) happiness arising from sleep, laziness and wrongdoing (taamsam’) Tamas (udaahrtam’) is said to be. (39)
Translation: The happiness which deludes the soul first at the time of experience and in the end, that happiness arising from sleep, laziness and wrongdoing, is said to be Tamas.