As for you, do not be called ‘Rabbi.’
You have but one teacher, and you are all brothers.
Now it is not only clear from this text (Matthew 23:8), but I have had it on authority from multiple sources that the word ‘Rabbi’ means ‘teacher.’
Hence the King James version of this same passage reads,
And do not be called teachers; for One is your Teacher, the Christ.
Now, what exactly is Our Lord saying here? Is this a case of Our Lord using hyperbole as he was sometimes known to do (e.g. “And if thy right eye offend thee, pluck it out, and cast it from thee”). So under this interpretation, he might be saying,
Don’t get puffed up and arrogant because of your various titles, especially those that indicate that you might have some kind of wisdom!
Or perhaps, along the same lines, our Lord is simply exhorting us to humility? As if he is saying,
Given that teachers and instructors tend to be intellectually proud, do not be called…