LEAVEN . The Hebrews and other peoples of the Middle East were taught to use leaven by the Egyptians, who may have discovered its use as early as 2600 bce. Although leavened bread took on importance as a religious symbol during the Azyme Controversy that finally divided Eastern and Western Christianity in 1054, the use of unleavened bread has had far greater significance in religious ritual. As a consequence, the ritualistic use of unleavened bread and the symbolic meaning of leaven merit special attention.
The best-known use of unleavened bread is described in the twelfth chapter of Exodus, where Ḥag ha-Matsot, the Feast of Unleavened Bread, and Passover are interfused in a historical commemoration of Israel's deliverance from Egypt. Other texts in the Hebrew scriptures indicate that the two feasts had different origins (Dt. 16:1–8, Lv. 23:5–6). Whereas Passover was a pastoral festival, the Feast of Unleavened Bread was agricultural. Because natural dough, a harvest gift of Yahveh, was considered holy, the addition of yeast would profane it. In addition, fermentation may have been viewed as a form of corruption.
Unleavened bread was prescribed for the night of Passover also to remind the Hebrews of the great haste with which they ate during their anxious flight from Egypt. During the Feast of Unleavened Bread, which began on the day following Passover and lasted seven days, the Israelites were directed to destroy all leavened bread that remained in their homes and eat only the "bread of misery."
When the Israelites celebrated Shavuʿot, the Feast of Weeks (or Pentecost), at the end of the wheat harvest, they offered leavened bread as first fruits because it had become their common bread in Canaan. Although they associated leavened bread with the giving of the Law of Moses, the ritual for communion sacrifices stipulated that unleavened cakes mixed with oil and unleavened wafers smeared with oil be used. Leavened bread, however, was also to be given to the priest for the sacrificial meal (Lv. 7:11–15).
The Israelites seem to have been ambivalent about adding leaven to dough. Although its use conflicted with their eating habits as nomads, once they settled in Egypt and Canaan they routinely consumed leavened bread.
In the New Testament, leaven has at least three symbolic meanings: It is a sign of the Old Covenant that must yield to the New Covenant; it is symbolic of corrupting influences; and it typifies small beginnings that have enormous potential for growth. Paul instructed the Corinthians to rid themselves of the old yeast of evil and wickedness and to become instead the unleavened bread of sincerity and truth (1 Cor. 5:8). In this way, they would be united with the risen Christ in an unending Passover. Paul thus turned the cultic practice of the Israelites into an ethical injunction. The suggestion that leaven corrupts is also found in the admonition of Jesus to be on guard against the yeast of the Pharisees, that is, their hypocrisy (Lk. 12:1). Like many other symbols, yeast had a positive as well as a negative aspect. The parable comparing the kingdom of heaven to a yeast that spreads through three measures of flour (Mt. 13:33) refers to the fact that something as small and unpretentious as yeast can have astonishing potential.
Plutarch recounts that in Greco-Roman culture, the priest of Jupiter was forbidden to touch unleavened bread because it was unclean and corrupt. For Philo Judaeus, unleavened bread was a symbol of humility and leavened bread a symbol of pride.
The bread used for the Eucharist was leavened in the Eastern church and unleavened in the Western rite. These geographical variations caused no difficulty until the Middle Ages, when the discrepancy gradually became a point of contention. It reached a climax in 1054 in the Azyme Controversy preceding the Great Schism that divided the Eastern and Western churches. Mohlan Smith, tracing the controversy in his book And Taking Bread, suggests that Eastern and Western liturgical traditions involving different types of eucharistic bread are based on an apparent disagreement in the scriptures about the date of the last supper. The synoptic gospels seem to indicate that the last supper took place on the first day of the Feast of Unleavened Bread. A reading of John, on the other hand, suggests that Jesus was crucified on the day of preparation. If this interpretation of John is accepted, the last supper would not have been a Passover meal, and leavened bread would have been used. The Eastern church's liturgical use of leavened bread also has theological overtones: It accentuates the break between the Old and New Covenants. Western rituals, on the other hand, emphasize the continuity of Hebrew and Christian traditions.
Smith, Mohlan H. And Taking Bread: Cerularius and the Azyme Controversy of 1054. Paris, 1978. An excellent study of the correspondence concerning the use of leaven in the eucharistic bread that was one of the issues in the schism between the Eastern and Western churches in 1054.
Wambacq, Benjamin N. "Les Massôt." Biblica 61 (1980): 31–54. A scholarly work that questions whether the Feast of Unleavened Bread was an agricultural feast.
James E. Latham (1987)
leav·en / ˈlevən/ • n. a substance, typically yeast, that is added to dough to make it ferment and rise. ∎ dough that is reserved from an earlier batch in order to start a later one fermenting. ∎ fig. a pervasive influence that modifies something or transforms it for the better: they acted as an intellectual leaven to the warriors who dominated the city. • v. [tr.] 1. [usu. as adj.] (leavened) cause (dough or bread) to ferment and rise by adding leaven: leavened breads are forbidden during Passover. 2. permeate and modify or transform (something) for the better: the proceedings should be leavened by humor [as n.] (leavening) companies of militia volunteers with a leavening of regular soldiers.
In the New Testament, leaven is a likeness of the potential for growth in the kingdom (Matthew 13. 33); but equally it is an illustration of the speed with which evil and corruption spread (1 Corinthians 5. 8; Luke 12. 1). Leavened vs. unleavened bread for the eucharist became a matter of dispute between the E. and the W. Churches: see AZYMITES.
of the same leaven of the same sort or character.
See also old leaven.
Hence vb. XV.