Rom Romans, chapter Epistle to the Romans, chapter 1
Because, even though they in actual fact knew G-d, they did not ascribe Him kavod (glory) as G-d or give hodayah (thanksgiving) to Him, but became filled with hevel (futility, vanity, emptiness, worthlessness) in their thinking, and their senseless levavot were darkened. Deu 28:29; Job 5:14; Isa 59:10; Eph 4:18