to the fact that the Bible unvaryingly uses leaven to symbolize something bad, unrighteousness, error, sin. Jesus referred to the leaven of the Pharisees and the leaven of Herod. (Matt. 16:6-12; Mark 8:15; Luke 12:1) The apostle Paul warns against the leaven that leavens the whole lump or mass. He refers to the typical festival of unleavened bread and clearly defines what leaven symbolizes, for he says: “Christ our passover has been sacrificed. Consequently let us keep the festival, not with old leaven, neither with leaven of badness and wickedness, but with unfermented cakes of sincerity and truth.”​—1 Cor. 5:6-8; see Deuteronomy 17:6, 7; 19:15; 1 Timothy 5:19; Hebrews 10:28.c

34. Accordingly, what does the parable of the leaven illustrate?

³⁴ In the face of this, Jesus did not make an exception with regard to the meaning of leaven when he gave the parable of the woman who hid a bit of leaven in three large measures of flour. In his consistency of teaching, he there used leaven to symbolize something unfavorable. So the parable must illustrate something unfavorable about matters having to do with the “kingdom of the heavens.” There the leavening of the big batch of dough pictures prophetically the corrupting of the professed Christian congregation with Babylonish error of teaching and practice. It pictures the symbolic leavening of what is illustrated by the full-grown mustard plant. Appropriately, then, both Matthew and Luke put the parable of the leaven right alongside the parable of the mustard grain, and Luke does so right after a stinging rebuke of hypocritical religionists.​—Luke 13:10-21.

Flight to the True Kingdom Refuge

1. (a) How has the organization pictured by the mustard-grain “tree” of Jesus’ parable been exposed? (b) How have most people in Christendom proved to be as described in Isaiah 6:8-10?

THE ORGANIZATION pictured by the “tree” that grew from the mustard grain in Jesus’ parable has been exposed by the worldwide preaching of Jehovah’s Christian witnesses. (Matt. 13:31, 32) Relatively few professed Christians have taken flight from that religious organization, namely, Christendom, and taken refuge under God’s Messianic kingdom proclaimed by Jehovah’s Christian witnesses. Like the prophet Isaiah of the eighth century B.C.E., these witnesses have gone and still go repeatedly to the peoples of Christendom,