I did this for awhile when I was in college, and I wouldn’t do it again. In my case, my friend was a musician, and led the music at this other church, and I liked listening to him play.
This is why I wouldn’t do it again. First, it is very easy to become a connoisseur of churches this way. You wind up judging what you like about one place and don’t like about the other. This is a bad habit, but hard to avoid. If you prefer the Catholic Church in every way, then you’re spending every Sunday morning in a more or less treacherous position, sort of looking down on the people who think you are a regular part of their community.
If you prefer the other church to the Catholic Church in some ways, then you are breeding discontent in yourself with your home church. You, meanwhile, can become in the back of your own mind the “rounded” Christian who has it all. Very bad.
Secondly, your friend is going to be put in a similar position: either become part of this new congregation, and in doing so reject you and the Church in some way, or else attend this other church while at the same time sitting in judgement of the people he worships with on a weekly basis.
And believe me, you yourself will disagree with what you experience there. Either the sermons will be vapid or they will say something substantial but oppose or pass over some important aspects of what the Church teaches. Then you’re doing damage control in re-catechizing your friend. The absence of the Eucharist will be jarring. The presence of something which pretends to be Holy Communion but is not valid is even worse, and you will not be able to participate in that in good conscience. Where are you then?
Every Christian community, whether Protestant or Catholic, deserves to have a real committed relationship at least possible with those who attend there on a regular basis. It is like a family. A period of courtship is permissible, but you don’t just drop in and “use” the place, as if it were a store or a movie theatre. I’m not talking about being a guest, as for a wedding or a funeral. I mean regular worship. They’re eventually going to deserve a deeper commitment. They deserve you to be either striving to be in unity as fellow believers or to go elsewhere.
Finally, if you’re giving time to this church, it is time you are not giving to your home parish. If you have that kind of time, they need you. Parishes don’t run on the people who are only willing to devote the little time it takes to show up for Mass on the weekend. That service is service you need to render, too. It makes of you a different sort of Catholic. It is a real grace to do it. (If you can’t do more, that’s different, of course.)
If your friend wants to go to a different church, you don’t necessarily have to discourage him, but don’t take him to a church you wouldn’t choose for yourself. Take him to the one you *did *choose for yourself. Give yourself to that church, too. Does he disagree with her some of the time? Well, guess what…some Catholics do, too. A lot, inf fact. A billion adherents to one religion don’t all march in lock-step. It doesn’t mean his objections are unimportant, but it is not as if he’s going to be shunned if he doesn’t accept everything about the Church right off the bat. He’s still welcome to inquire. Encourage him to come to Mass, then, with the full understanding that no one expects the road to Rome to be travelled in a day.
Evangelize by being the best Catholic you can be. Don’t split yourself off into this other venture. It isn’t the best witness.
