Divisions among Christians in the city of Corinth -
"Now I beseech you, brothers, through the name of our Lord Jesus Christ, that you all speak the same thing and that there be no divisions among you, but that you be attuned in the same mind and in the same opinion.
For it has been made clear to me concerning you, my brothers, by those of the household of Chloe, that there are strifes among you.
Now I mean this, that each of you says, I am of Paul, and I of Apollos, and I of Cephas, and I of Christ.
Is Christ divided? Was Paul crucified for you? Or were you baptized into the name of Paul ?" (1:10-13)
The believers were exalting in competition champions to the extent that neglected their union with the living, available Jesus Christ.
This is NOT about teachers are wrong in and of themselves.
This is about NO teacher no matter how useful or gifted or how blessed his or her ministry can replace Christ Himself.
I have not overlooked that the last name mentioned is Christ -
"Now I mean this, that each one of you says, I am of Paul, and I of Apollos, and I of Cephas, .... and I of Christ."
The last group of the divisive ones is the most subtle. What they mean, in Corinth, is that they are of Christ in an exclusive way and other Christians in Corinth are not of Christ.
It sounds good. But it too is divisive in terms of the one local church which should cover the whole city of Corinth.
"Paul, a called apostle of Christ Jesus through the will of God, and Sosthenes the brother, to the church in Corinth ..." (1:1)
The [singular] church in Corinth.
In Corinth there is one church. It is the truly local church - tied to the locality of the city Corinth. The Christians living in Corinth constitute the church in Corinth.
Paul firstly addresses the problem of the divisions in the practical unity of the local church.