LEAVEN (lĕv'ĕn, Heb. se’ōr, hāmēts, Gr. zymē). The answer to seven questions will cover most of the biblical material.
2. Why was leaven permitted in certain other offerings (Exod.23.15-Exod.23.16; Exod.34.22-Exod.34.23; Lev.2.11; Lev.7.13-Lev.7.14; Lev.23.17-Lev.23.18; Num.15.20)? The answer seems to be that leaven, a part of the daily food, is included in the offerings of thanks. Some hold that leaven here symbolizes the evil that still inheres in the worshiper.
3. Why was leaven excluded from the Passover (Exod.12.14-Exod.12.20; Exod.23.15; Exod.34.18; Deut.16.2-Deut.16.4)? The record indicates that Israel’s haste in leaving Egypt prompted this exclusion (Exod.12.11, Exod.12.29; Deut.16.3). However, the Passover as a type of Christ, who was wholly free of corruption, must be taken into account here (cf. 1Cor.5.7-1Cor.5.8).
4. Does Lot’s use of unleavened bread (Gen.19.3) anticipate the symbolism of the Sinaitic legislation? Haste may have been the reason; but the latent symbolism of evil (as inconsistent with angels) cannot be entirely ruled out.
5. What does Amos.4.5 indicate? That the degenerate northern kingdom mixed the permitted (Lev.7.13; Lev.23.17) with the forbidden (Exod.23.18; Exod.34.25; Lev.2.11).
6. What about the NT significance of leaven? Apart from Matt.13.33 (see below), leaven symbolizes either Jewish legalism (Matt.16.6, Matt.16.12; Gal.5.9) or moral corruption (1Cor.5.6ff.).
7. What, then, about Matt.13.33? This is a much-disputed passage. Some interpret leaven as symbolizing the final apostasy of the professing church; others explain leaven as symbolizing the permeating effect of the gospel in Christianizing the world.——WB
Bread was made to rise by putting a piece of sour dough from a previous batch of dough in the flour, which dough in turn brought on fermentation of the whole. Leavened bread was a regular part of the diet of ancient Israel (Hos 7:4). Bread made in haste without rising is called “unleavened bread” (Maṩṩot, LXX azúmē, Vul. Azyma; Gen 19:3; Exod 12:15; Judg 6:19; 1 Sam 28:24; etc.). The haste to depart from Egypt left no time for bread to rise, therefore the people carried with them dough and kneading troughs (Exod 12:34, 39).
This prohibition of leaven was interpreted to prohibit that which is fermented from grain rather than that from the grape (M. Passover 3:1). There is no mention in the Mishna of wine lees as leaven. The prohibition of leaven did not prohibit the drinking of wine at passover. The rabbis ruled that the poorest man in Israel was entitled to four cups even if it had to be supplied by charity (M. Passover 10:1).
The significant thing about leaven is its power, which power may become a symbol of either good or evil. Jesus, in the parable of the leaven (Matt 13:33; Luke 13:21) used the working of leaven to teach the pervasiveness of the kingdom which eventually transforms the world. The small bit of leaven—the Word—has power to accomplish this great result. The final point of the comparison is the whole lump permeated by the leaven. This parable is one of a pair with the parable of the grain of mustard seed. Philo (Spec. Leg. II. 184f.) seems also to use leaven as a symbol of something good. Scofield et al., on the other hand, insisting that leaven in Scripture is always a symbol of evil, attempts to make the parable a picture of the true teaching being mingled with corrupt and corrupting false doctrine resulting in the final apostasy of the professing church. One’s approach to this issue is ordinarily determined by a prior decision on the question of whether the NT outlook for the kingdom is optimistic or pessimistic.
Leaven also is a symbol of undesirable teaching used by Jesus in warning against the “leaven of the Pharisees and Sadducees” (Matt 16:6, 11, 12). The parallel in Luke 12:1 reads: “the leaven of the Pharisees which is hypocrisy.” This interpretation turns aside any possible misunderstanding that Jesus is warning against the bread of the Pharisees as the rabbis warned against the “leaven or meat” of the Samaritans which is interpreted by some rabbis to be a warning against mixed marriages (SBK I. 541f.). Mark 8:15 has a warning against the “leaven of the Pharisees and the leaven of Herod [or some MSS ‘Herodians’].” Leaven as a symbol of the undesirable is paralleled in the rabbis who called the evil desire (yeṩer hara’) the leaven that is in the dough” (T. B. Ber. 17a; Gen. R. 34:12).
Paul uses leaven as a symbol of the pervasiveness of evil (1 Cor 5:6) and makes an allegory on the casting out of leaven at Passover. Here malice and evil are the leaven which need to be replaced by sincerity and truth that the festival may be celebrated (1 Cor 5:7, 8). Paul also uses leaven as a symbol of evil which has power to influence the whole as he cites the proverb “a little leaven leavens the lump” (1 Cor 5:6; Gal 5:9).
SBK (1926), I, 728; H. Windisch, “Zume,” TWNT (1935); II, 904-908; J. Jeremias, The Parables of Jesus (1955), 89, 90.
International Standard Bible Encyclopedia (1915)
(1) In Bread-Making.
The form of leaven used in bread-making and the method of using it were simple and definite. The "leaven" consisted always, so far as the evidence goes, of a piece of fermented dough kept over from a former baking. There is no trace of the use of other sorts of leaven, such as the lees of wine or those mentioned by Pliny (NH, xviii.26). The lump of dough thus preserved was either dissolved in water in the kneading-trough before the flour was added, or was "hid" in the flour (the King James Version "meal") and kneaded along with it, as was the case mentioned in the parable (Mt 13:33). The bread thus made was known as "leavened," as distinguished from "unleavened" bread (Ex 12:15, etc.).
(2) In Law and Ritual.
(3) In Teaching.
The figurative uses of leaven in the New Testament, no less than with the rabbins, reflect the ancient view of it as "corrupt and corrupting," in parts at least, e.g. Mt 16:6 parallel, and especially the proverbial saying twice quoted by Paul, "A little leaven leaveneth the whole lump" (1Co 5:6 f; Ga 5:9). But as Jesus used it in Mt 13:33, "The kingdom of heaven is like unto leaven," it is clearly the hidden, silent, mysterious but all-pervading and transforming action of the leaven in the measures of flour that is the point of the comparison.
Nowack, Hebrew Arch., II, 145 f; Talmud, Berakhoth, 17a; Lightfoot, Hor. Hebrew. on Mt 16:6.
George B. Eager