एषावृतिर्नाम तमोगुणस्यशक्तिर्यया वस्त्ववभासतेऽन्यथा ।सैषा निदानं पुरुषस्य संसृते -र्विक्षेपशक्तेः प्रसरस्य हेतुः ॥ ११५ ॥
In plain words
This is what is called the veiling power of tamas - the power that makes a thing appear to be something other than what it really is. And this very veil is the root of every person's bondage to the cycle of birth and death; it is also what lets the projecting power run wild.
Close to the Sanskrit
This is called the veiling power of the tamo-guṇa — the power by which a thing appears otherwise [than it really is]. This same [power] is the root-cause of a person's transmigratory existence, and the cause of the spreading forth of the projecting power.