Agreeing with @Salieri. Say what he suggests. It's not really appropriate for a Mass on any occasion, anyway.

I have no problem asking folks to substitute something else when I don't know the piece. You said you don't know it, so listen here. It sounds difficult.

https://www.youtube.com/watch?v=qoAcHt5o24M

Incidentally, it's a love song, but not religious, so it doesn't belong at Mass anyway. (This is a reason I would not mention unless necessary.) Here are the lyrics.

If they wanted someone to sing it at the wake, that would be fine, if the funeral home has a suitable piano and if the family is willing to pay for a "collaborative pianist" to accompany the singer.

My job doesn't depend on it, so I'd just say 'no'. Other options:

"I can't do it justice without a 96-piece orchestra"

"I can't do it without draping myself over a handsome, unshaven, blind, Italian man"

"I don't have the dress for that song"

"That song has an A flat. I don't sing A flats."

I'm joking, of course -- couldn't help it -- but really, if you are not going to tell them that the song just is not appropriate for mass (and I understand the pressure not to say so), then I agree with the suggestion to tell them that you just 'cannot' do it. There's no reason to elaborate on the meaning of 'cannot'. If they ask why, it is easy to be evasive ("I just don't have that in me...."). They'll chalk it up to 'whatever' and think less of you, but who cares?

Btw, welcome, mamaherrera. I was being a bit tongue-in-cheek above, and having trouble with html.

I usually tell people outright that it isn't appropriate for mass, and usually they are fine with it. Lately, when planning weddings and funerals I tell people that if they have any specific requests to let me know and I'll try to work them in. I also include "Please don't feel like you must find music for all parts of the mass, that's my job. Just let me know if you know of anything specific that you might want."

" I would not sing it well because I don't know Italian.... so you really wouldn't want me to sing it."

If you are new, people try very hard to see what they can get you to agree to. Then they will use it against you every time someone in their family or a friend has a funeral at your church (been there, done that). My advice is to put your foot down - the song is not appropriate for Mass. or better yet, that song is not allowed during the funeral Mass. They will understand and even if they don't understand, there is a 98% chance they will be polite to your face and only stew about it behind your back. Either way, you will have established that you are the authority in this situation.

For what it's worth, there are lots of ways I try to incorporate family wishes and offer them up front so that I establish good will with a grieving family from the outset. Then, when I say no to some other request, it feels like no big deal to them because I've shown myself to be helpful in other ways.

Incidentally, my username comes from the name of a cruise ship string quartet that would play, among other things, "Time to Say Goodbye." I was in middle school, dress up for formal dinner early, and go listen to them play before my family arrived. Formative is the word I'd use. I love the tune, but would be horrified to hear it at a funeral (especially after Donald Turkington's Requiem last week).

Two weeks ago, we had a funeral for a Catholic man whose family was in various stages of no longer practicing. The widow asked for "Danny Boy." I was glad the pastor told her that the funeral mass was a sacred rite of the Church, and secular music was not appropriate.

I like the Bocelli/Celine Dion version of "The Prayer" better. If I have to pick cheesy pop stuff LOL