This image, which Caravaggio may have painted for Olimpia Aldobrandini, takes as its starting point a passage from the Gospel of Luke in which Christ has been welcomed into the house of sisters Martha and Mary Magdalene. It shows an imaginary exchange between the modest Martha, shown reproaching her sister for her wayward conduct and enumerating on her fingers the miracles of Christ, and the sensual, vain Mary, who wears luxurious clothing and rests her hand on a large mirror.
However, Caravaggio introduced details that hint at Mary’s forthcoming conversion. In her right hand, she holds an orange blossom twig, a symbol of purity; the ring on her left hand alludes to her status as the bride of Christ. PThe lavishly attired Mary Magdalene is caught in a moment of reflection, resting her hand on a convex mirror. The mirror may be a reference to the ‘mirrored shield’ used by Caravaggio in his artistic practice and recorded in the 1605 inventory of his goods.
The Arts of Golden Age Spain and the Hispanic World 