Jerusalem’s Bible Lands Museum presented what it termed as the oldest known Jewish prayer book, or siddur, at a closed ceremony Thursday evening. The tiny manuscript, about the size of an iPhone 4s, is estimated to be 1,200 years old, and is about 50 pages long, with Hebrew script covering each thick, rough-edged page.

The Siddur (prayerbook) of Saadia Gaon is the earliest surviving attempt to transcribe the weekly ritual of Jewish prayers for weekdays, Sabbaths, and festivals (apart from the prayer book of Amram ben Sheshna, of which there is no authoritative text).