The number 120 symbolizes a complete period of time, human lifespan, and spiritual fulfillment in biblical tradition.
In Genesis 6:3 God sets the human lifespan to 120 years, and according to the Bible Moses lived exactly 120 years (Deuteronomy 34:7). Moses' life is traditionally divided into three periods of 40 years – in Egypt, in Midian, and as Israel's leader – which underscores the number's composition of three times forty, a measure of complete testing and maturation. In the New Testament there were 120 believers gathered in the upper room when the Holy Spirit was poured out on Pentecost (Acts 1:15), and the number thus also marks the beginning of the church age. In this way 120 frames both the full measure of human life and a spiritual completion that extends from creation to the start of the new covenant. The Hebrew expression "ad me'ah ve'esrim" (עד מאה ועשרים), meaning "to 120," is still used as a Jewish blessing and wish for a long life. It is also known in Yiddish form as "bis hundert un tsvantsik". According to rabbinic tradition (Mishnah, Avot 5:21), the Great Assembly (Knesset HaGedolah), founded by Ezra after the exile, consisted of 120 members. This body is considered the source of many liturgical and halachic traditions. Some rabbinic sources link the number 120 to the period of 120 years that Noah spent building the ark, as a time of grace for humanity to repent before the flood (Sanhedrin 108b).*