Paul asked the Galatian church, "Ye did run well; who did hinder you that ye should not obey the truth? This persuasion cometh not of him that calleth you. A little leaven leaveneth the whole lump" (Galatians 5:7-9).
Paul is referring here to a mindset, a doctrinal belief or point of theology. He is asking, "What's in your life that keeps you from going on in the full blessing of Christ? You were doing so well at one time. I know you to be a praying people, and you labor diligently to do good works, but something is wrong. I don't see you growing anymore. Instead, you've gone back to relying on your flesh. I don't sense the sweet aroma of Christ you once had. Your certainty, your clarity, your vision are all gone. Something's hindering you.
"What could have persuaded you to settle in this condition? Whatever it is, I tell you it's not of God. In fact, I sense leaven in you, a compromise of some kind. Something is clouding you, something you may be holding on to. And it's causing the Lord to have a controversy with you. Tell me, what is it?"
I know so many Christians today who once were mightily used of God. These people were devoted, praying, believing saints. But then something happened to them that somehow caused them to be hindered from experiencing the fullness of the blessing of Christ.
This includes many ministers I know. These men saw victory after victory in their walk with the Lord. But something crept into their lives, some compromise, and over time they made peace with it. Often that hindering leaven was a single besetting sin.
To all such people, Paul asks, "What happened? What's hindering the flow of Christ's blessing in your life? What leaven has crept in?"
Paul finished this passage by warning the Galatians, “A little leaven leaveneth the whole lump” (Galatians 5:9).