Bhagavad Gita · 18.39

यदग्रे चानुबन्धे च सुखं मोहनमात्मनः।निद्रालस्यप्रमादोत्थं तत्तामसमुदाहृतम्॥

yad agre chānubandhe cha sukhaṁ mohanam ātmanaḥ nidrālasya-pramādotthaṁ tat tāmasam udāhṛitam

That happiness which deludes the self both in the beginning and in the end, arising from sleep, laziness, and negligence — that happiness is declared to be tamasic.

— Bhagavad Gita 18.39

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)