The Prophet Muhammad said: 'This is the source of the tradition of the Sa'y (One of the rituals of the hajj, or pilgrimage) the going of people between them (i.e. As-Safa and Al-Marwa). When she reached Al- Marwa (for the last time) she heard a voice and she asked herself to be quiet and listened attentively. She heard the voice again and said: '0, (whoever you may be)! You have made me hear your voice; have you got something to help me?' And behold! She saw an angel at the place of Zam-zam, digging the earth with his heel (or his wing) till water flowed from that place. She started to make something like a basin around it, using her hand in this way, and started filling her water-skin with water with her hands, and the water was flowing out after she had scooped some of it."
The Prophet added: "May Allah bestow mercy on Ishmael's mother! Had she let the Zam-zam (flow without trying to control it or had she not scooped from that water to fill her water-skin), Zam-zam would have been a stream flowing on the surface of the earth."