The Number Forty

If seven is the number of completion, forty is the number of waiting. In the Hebrew Bible it marks the long stretch between an old state and a new one. Rain falls on the earth for forty days and forty nights before the Flood begins to recede. Moses stays forty days on Mount Sinai to receive the Law, and after the golden calf he returns for another forty. The spies sent into Canaan scout the land for forty days, and because the people refuse to enter it, they are condemned to wander forty years, one year for each day, until the generation that left Egypt has died.

The pattern repeats on a smaller scale. The prophet Elijah walks forty days to the mountain of God. Jonah warns Nineveh that it will be destroyed in forty days. Goliath challenges Israel for forty days, and David and Solomon each reign forty years. Later Jewish writers noticed that Moses’ life of 120 years falls into three forties, an idea the New Testament book of Acts repeats. Most scholars read these as round numbers, a way of saying “a full span of time”, rather than exact counts.

The New Testament takes up the pattern on purpose. Matthew, Mark and Luke all say that Jesus fasted in the wilderness for forty days before beginning to preach, an echo of Moses and Elijah that early readers would have caught at once. Acts adds that the risen Jesus appeared to his followers for forty days before the ascension.

Lent grew out of that wilderness fast. The earliest Christians fasted for a day or two before Easter; by the time of the Council of Nicaea in 325, a forty-day season was being mentioned, and it became the norm across the church during the fourth century. Counting the days took some ingenuity. In the West, Lent runs from Ash Wednesday to Holy Saturday, forty-six days, because Sundays, as weekly feasts of the resurrection, do not count as fast days. Eastern churches begin earlier and reckon the forty days in their own way.

Islam knows many of the same biblical forties. The Qur’an speaks of Moses’ appointment with God over forty nights and of the Israelites wandering forty years. It also calls forty the age at which a person “reaches full strength” (46:15). Islamic tradition holds that Muhammad was about forty when he received his first revelation in the cave of Hira, near Mecca, around 610 CE, and Muslim scholars have long seen this as the age of maturity and prophetic calling. Hadith collections called “the Forty”, such as the famous one compiled by al-Nawawi in the thirteenth century, reflect a report that the Prophet praised whoever preserved forty traditions for his community.

Forty also shapes the rhythm of grief. In Eastern Orthodox churches, and in Romania, Greece, Russia and the Middle East, families hold a memorial service on the fortieth day after a death; popular belief holds that the soul’s journey is completed by then. Many Muslim communities, from the Balkans to Iran and South Asia, also mark the fortieth day. For Shia Muslims, Arba’in, forty days after the anniversary of the death of Husayn at Karbala in 680 CE, draws one of the largest pilgrimages in the world to his shrine. A matching custom surrounds birth: Leviticus sets a forty-day period of purification after the birth of a son, Mary’s presentation of Jesus in the Temple is celebrated forty days after Christmas, and many Mediterranean and Middle Eastern cultures keep mother and baby at home for forty days.

The most famous legacy of forty is a word. During the plague epidemics of the fourteenth century, the city of Ragusa, today’s Dubrovnik, ordered in 1377 that travellers from infected areas spend thirty days in isolation before entering. Venice and other ports later adopted the measure and lengthened it to forty days, quaranta giorni, from which English gets “quarantine”. Why forty? Historians do not agree. Medical theory of the time, inherited from Greek physicians, treated forty days as the limit of an acute illness, and the religious associations of the number, from Lent to the wilderness, would also have made it feel right. Both explanations may be true at once.

Elsewhere forty lives on in quieter ways. Sikh tradition tells of forty soldiers who abandoned Guru Gobind Singh during the long siege of Anandpur (1704–1705), signing a statement that they were no longer his followers. Shamed at home, they returned under the leadership of a woman, Mai Bhago, and fell defending the Guru at Khidrana, renamed Muktsar, “the pool of liberation”. The story holds that the dying leader asked the Guru to tear up the statement, and he did. Sikhs recall these Forty Liberated Ones in their daily prayer and at an annual fair at Muktsar. Hindu devotees recite forty-verse hymns called chalisa. The Greek poet Hesiod had already noticed that the Pleiades disappear for about forty days each year, and later writers pointed to the roughly forty weeks of human pregnancy. None of this proves why the number first mattered, but it suggests why it kept seeming natural: forty is long enough to change a person, and short enough to be lived through.