The feast begins. Thaïs arrives and sings a bittersweet love duet with Nicias: this is their last night together. She then asks him about Athanaël, who overhears her and tells her that he has come to teach her "contempt for the flesh and love of pain." Not tempted by this proposition, she offends his sense of propriety with a seductive song. He leaves, angrily promising to come back later, while she taunts him with a parting shot: "Dare to come, you who defy Venus!" and begins to disrobe as the curtain falls.