[agere_contra]

Cephas means “Rock”.

I seem to remember it’s a hard C, like KEY-phas. If that’s true, it sounds a bit like like the ringing sound you get from striking stone with a hammer.

[expat2]

OK, the Aramaic word for 'Rock' is pronounced something like Kiapa so apparently in Aramaic 'Peter's' name does mean 'Rock'.
So it appears that Jesus was indeed making a play on words, and the interpretation that he meant to charge Peter with being the lead man in spreading his Church is the correct one.