Hai ben Sherira Gaon, a medieval Jewish Rabbi and scholar living from 939 to 1038, recounted experiences of elders confronting the dream question. He recalls several pious elders who fasted, prayed, meditated, in order to go to sleep and receive prophetic revelations. Moshe Idel comments on this, noting that the practice of She’elat Halom calls for the aspirant to fast, pray, and recite verses. He referred to several elders who would fast for a few days, maintain a state of purity through prayer, and recite the letters of verses by their numbers. In their dreams, they would encounter wondrous answers, comparable to prophetic visions. In some cases, however, questions have been answered in dreams without prior fasting and ritual purification involved. During the high middle ages, the dream question was often utilized by (mainly
Ashkenazi) Rabbis to determine Jewish law. This process was highly at odds with the
Sephardic (
halakhic) rationalism that was represented by
Maimonides. R. Eliezer B. Nathan (Raban) of
Mainz recorded his experience with the dream question in 1152. On Shabbat, he had inquired out loud, wondering if a glass used to drink wine by a gentile could then be used for Jewish wine consumption. He then took a nap and in a dream, his late father in law came to him and recited verses from the
books of Amos and
Isaiah that answered the question he asked earlier. The glass was not fit for Jewish wine consumption because residue from the wine consumed by a Gentile was still present on the glass. In medieval Jewish literature, there is a distinct difference between the dreams from the She'elat Halom practice that occur in the beginning of the night versus at the end of the night. Dreams at the beginning of the night tended to lack prophetic contents whereas dreams at the end of the night were usually revelatory with divine interventions. In their autobiographical writings from the early 17th century, both mystic
Hayyim Vital and rabbi
Leon of Modena claim matter-of-factly to have asked a dream question. ==The use of numbers==