When you know how the story’s going to turn out, the first time you encounter this in Joshua you can’t help but cringe. And then, every subsequent time it happens there seems to ring an ominous bell tolling a warning that this just won’t turn out well.

And my combination of readings this morning remind me that was true way, way back then, when Joshua was leading the people into the land, and what was true way back then, when Paul was writing to the Corinth church, is true today as well. A little leaven leavens the whole lump.

The first cringe worthy encounter during this morning’s ready occurred in Joshua 13.

Yet the people of Israel did not drive out the Geshurites or the Maacathites, but Geshur and Maacath dwell in the midst of Israel to this day.

(Joshua 13:13 ESV)

And it’ll happen again in chapters 15, 16, and 17. For whatever reason, God’s people are not able to rid the land of the old ways. God had told them through Moses to “devote to destruction” all that breathed in the cities the LORD was giving them, “that they may not teach you to do according to all their abominable practices that they have done for their gods, and so you sin against the LORD your God” (Deut. 20:16-18).

And that’s how things started with conquering the land–a clean sweep. But then, for whatever reason, complete victories became partial victories and increasingly the people and practices of the land took root in their midst.

And, if you know the rest of the story, it just didn’t turn out well. The remnant which should have been dispossessed became thorns in the sides of God’s people. Their gods becoming a snare entrapping them in spiritual infidelity. And, within a generation, everyone ended up doing what was right in their own eyes. (Judges 2:3, 17:6)

Fast forward centuries to Corinth and the thorns and snares continue to compromise the people of God.

Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our Passover lamb, has been sacrificed. Let us therefore celebrate the festival, not with the old leaven, the leaven of malice and evil, but with the unleavened bread of sincerity and truth.

(1Corinthians 5:7-8 ESV)

The Corinthian Community Church, while have a lot going for it, apparently put up with some stuff they shouldn’t have. While boasting of it’s loving tolerance, it ended up tolerating the wrong thing. Something that, left unchecked, would spread. Something that, if not addressed, would bring increasing compromise.

Though they were a “new lump”, a body of new creations in Christ, if the old leaven of malice and evil was not dealt with it would spread and choke out the new way of walking in sincerity and truth. And, just as it had with God’s ancient people, if they refused to eradicate the ways of the world that encroached from without they would, without doubt, eventually crumble from within.

How come?

Do you not know that a little leaven leavens the whole lump?

(1Corinthians 5:6b ESV)

How we as the church today need to be aware of this eroding dynamic.

In an age where the pressure has never been greater to bow to the world’s subjective, untethered views of truth, and when the terms tolerance and endorsement have become synonymous, we need great discernment as to how to love the world but not be infected by the world.

And part of that discernment is protecting the purity of the body of Christ. To deal with the old leaven of malice and evil when it’s detected. To lovingly, yet firmly, call brothers and sisters to repentance. To engage in other’s lives with a view of being used in their restoration. That we might celebrate together Christ our Passover “with the unleavened bread of sincerity and truth.”  To promote the healthy, life-giving, fruit-producing leaven of being who we are in God’s Son and of standing firm for what we believe on the authority of God’s word.

By His grace. For His glory.