In 1771, during the Fourth Mexican Provincial Council, the advocation of Holy Mary Mother of the Light was at the core of a heated debate. Both devotional practices and the widespread circulation of that image, besides treatises on the cult and the arguments of those attending the Council, revealed a complex situation going beyond strictly religious matters. Even though the discussion was around the power images have for “teaching truth” and making “alive that which is certain,” the control on the doctrinal orthodoxy and the devotional practice was aimed at the regulation of the faithful's response when in front of the image. Thus, the statements of advocates and detractors provide grounds for examining the profound interaction between art theory and the theory of the religious image.