Division

 for there must be factions among you in order that those who are genuine among you may be recognized.
1 Corinthians 11:19 ESV
https://bible.com/bible/59/1co.11.19.ESV

This is a surprising verse for 1 Corinthians, a book whose main reason of writing was to challenge divisiveness. In this verse, Paul seems to acknowledge the inevitability of division. This is in harmony with Jesus's teaching about the likes of wheat and chaff, and sheep and goats.

Of course, the true Church of Christ with a capital T is, and should be, united in worship of Him. However, local churches are often populated by a motley crew of genuine believers and professing Christians who aren't necessarily the genuine article. This was seen most clearly at the communion table in the Corinthian church.

It seems the Corinthian church met in the villa of one of their wealthier members. What was happening was that the rich members had places at the top table and were over eating and drinking at communion. Meanwhile, the slaves out in the courtyard were going hungry and thirsty.

Clearly, what was going on was wrong. Thankfully, in most churches nowadays, the communion table is open to all professing believers. Paul warns those who take communion to have regard for one another.

'Lord, please help us in our churches, to be united around Christ, and to treat one another equally. For Your honour and praise we pray, amen'