Presuming you're not a Catholic, aren't you a tad bothered by celebrating
If you want to start a thread on the pagan origins of Catholocism, by all means, you go right ahead. I've got my hands full with this one.
If you can show me that the word "mass" has pagan origins, then, yes, I might be a tad bothered by it. But at least Christ is acknowledged in there SOMEwhere.