Bakers and good cooks know that yeast not only makes pastries rise, it also makes them tasty. Without yeast, bread would be flat and bland. The Bible portrays yeast as both a positive and a negative symbol. In 1 Corinthians Chapter 5, the Apostle Paul uses yeast in a negative sense—to show what can happen when a church fails to deal with members that commit gross sinful deeds. The example he uses is that of a church member who was sleeping with his stepmother, a practice that even unbelievers did not tolerate. Paul’s concern was that unless the church dealt with this issue, it would not only hurt the person doing it, it would also hurt the entire church. It would be like yeast that spreads quickly in dough, or like cancer that spreads and destroys good tissue, causing a person to die prematurely. Paul realized that the spiritual life of this professing believer was being sapped by this wicked behavior; Paul also knew that the integrity of the larger flock was at risk. So he advised the church to call a meeting and deal with the situation. They were to exclude the man from fellowship until he repented and abandoned his wicked behavior.