The problem is yeast, Pharisee-Sadducee yeast.” Then they got it: that he wasn’t concerned about eating, but teaching – the Pharisee-Sadducee kind of teaching.” Matthew 16:11–12 MSG
“Yeast cells thrive on simple sugars. As the sugars are metabolized, carbon dioxide and alcohol are released into the bread dough, making it rise.” In the same way that yeast disappears into a batch of flour only to show up a while later bad teaching can be received and thought to be forgotten until it shows up with some nasty results.
The particular bad teaching that Jesus was warning His disciples about was that our performance qualifies us for acceptance to God. A good Sunday of dutiful worship and kind deeds makes us more acceptable to God than that Monday morning when you argue with your spouse, shout at the crazy motorcyclist weaving through traffic, get upset with your unfair boss and grumble about the tepid chai in the cafeteria. As Jerry Bridges says in his outstanding book ‘Transforming Grace’ we get onto this performance treadmill and can’t get off. We buy into the lie that our performance is the basis of our relationship with God. This is a subtle lie that creeps in and ruins our life
We get accepted before God on the basis of grace alone. We are saved by grace through faith (Eph 2:8–9) and if we add any performance to that we then fall from grace (Gal 5:1–3) and are cut off from Christ. Some of us understand that the entry into Christ is through grace but think then that we have to perform to stay acceptable. Romans 5:1–3 denies that saying that we still ‘stand in this grace’ that daily this is the only basis everyday of acceptance before God. This means I am as acceptable on that foul Monday as I was on the good Sunday. My performance does not make me more or less acceptable to God.
In the law the people were commanded to offer a sacrificial lamb to atone for their sin. When the repentant sinner brought his sacrifice to the priest it would be examined carefully to ensure there were no defects. During this examination everyone was focussed on the lamb. The priest, the repentant sinner, all the other priests and repentant sinners waiting for their sacrifices to be examined – everybody’s gaze was on the lamb. The repentant sinner would heave a sigh of huge relief when the priest stamped his sacrifice as acceptable. In the same way Jesus is God’s Lamb given for the sins of the whole world. And just as the lamb was the focus of everybody’s attention so Jesus should be the focus of our attention everyday. And Jesus is the perfect Lamb that was totally acceptable to God making us acceptable too.
Life therefore is not to be lived looking at our performance for acceptance before God. Life is to be lived by looking at Jesus as the perfect sacrifice making us totally acceptable to God on all days, good Sundays and bad Mondays alike. This is the good yeast that we need to receive and have it flood our souls and affect our whole life.