The Immaculate Conception is a Roman Catholic dogma that asserts that Mary, the mother of Jesus, was preserved by God from the stain of original sin at the time of her own conception. Some theologians have asserted this special grace extended to impeccability (understood in this context as the inability to sin); others argue this could not be so: as a natural human being, she would have had free will, and therefore the "ability" to sin, but through her cooperation avoided it.