The most significant source for the devotion to the Sacred Heart in the form it is known today was a nun of the religious congregation of the Visitation of Mary Saint Margaret Mary Alacoque (1647-1690), who claimed to have received visions of Jesus Christ. There is nothing to indicate that she had known the devotion prior to the revelations, or at least that she had paid any attention to it. These alleged revelations were numerous, and the following apparitions are especially remarkable: