 Razi based his hypothesis on the fact that some of the poetry of the early Islamic era refers to Mihragan in connection with snow and cold.Razi's theory has a significant following on the Internet, but while Razi's documentation has been academically accepted, his adduction has not.Sufism's "Chella", which is a 40-day period of retreat and fasting, is also unrelated to winter solstice festival.