One of Albert's greatest contributions was his study of Dionysus the Areopagite, a mystical theologian whose words left an indelible imprint in the medieval period. Magnus' writings made a significant contribution to German mysticism, which became vibrant in the minds of the Beguines and women such as Hildegard of Bingen and Mechthild of Magdeburg. Mysticism, for the purposes of this study, refers to the conviction that all believers have the capability to experience God's love. This love may manifest itself through brief ecstatic experiences, such that one may be engulfed by God and gain an immediate knowledge of Him, which is unknowable through the intellect alone.