Yeast is known world-wide. It is used in brewing, to convert sugars into alcohol; and in baking, to produce carbon dioxide which lightens or ‘leavens’ the texture of bread. Yeast cells grow at an amazing rate, budding off ‘daughter cells’ which also grow and bud. It only requires a little yeast in the right growing conditions to eventually produce millions of yeast cells which have a powerfully increased effect. Paul used yeast as an illustration to show how easily false teaching can spread through a church and change it.
 
Wrong teaching, saying that circumcision was essential if Christians were to be accepted by God, had spread like yeast. It had a powerful effect in people’s minds, and Paul was persecuted harshly for saying that their teaching was wrong. He knew that people are only made right with God when they believe in Jesus Christ and accept His sacrifice as payment from their sins. But false teaching is not only dangerous for people who tell the true gospel, it brings the penalty of God’s judgement, even though people may be sincere: if they are wrong, God holds them accountable.
 
The only way to identify and eliminate false teaching is to know the truth; then the lies can be rejected. That was why Paul spent so much time in this letter explaining which teachings are true and which are false. The Bible continues to give us God’s standard for truth in every area of life and doctrine. That is why Word@Work is produced, to enable Christians all over the world to choose to embrace the truth and reject the lies. So each of us need to be constantly alert and not naïve; the devil is called the ‘father of lies’ and he continues to ensure that they are spread everywhere, including where you are today.