His basic concern is that providing assistance to illegal immigrants would violate this law. The logical question is, what is meant by "assistance?" Well, from a plain reading of the bill (HR 4437) it would seem that the following things would be illegal: (all references are to 8 USC 1324 as it would be ammended by HR 4437)
1) Providing a meal at a soup kitchen. (8 USC 1324 sec 274 (a) (1) (C) - makes whoever "assists, encourages, directs, or induces a person to reside in or remain in the United States, or to attempt to reside in or remain in the United States, knowing or in reckless disregard of the fact that such person is an alien who lacks lawful authority to reside in or remain in the United States" a criminal)
2) Putting up an illegal immigrant in one's home or even in a homeless shelter. (see (1) above)
3) Providing medical assistance. (see (1) above)
4) Giving them a ride to the other side of town. (8 USC 1324 wec 274 (a) (1) (D) - makes whoever "transports or moves a person in the United States, knowing or in reckless disregard of the fact that such person is an alien who lacks lawful authority to enter or be in the United States, where the transportation or movement will aid or further in any manner the person's illegal entry into or illegal presence in the United States" a criminal) -- an woe to the taxi driver who does this for commercial profit!
So apparently we're supposed to check greencards of our parishoners or our neighbors before we do any of these things. Otherwise face possible prosecution and up to 5 years in prison and/or a fine. And the poor taxi driver could face up to 20 years in prison!
The good thing is that the core ministry of Word and Sacrament don't appear to be covered by this legislation. So with the exception of providing the Lord's Supper which might possibly be construed as "assisting" or "encouraging".
I know, the good cardinal is being a bit alarmist about this, and this post too takes the bill far more literally than the courts would (hopefully)... But it makes you think about how many laws you might already be breaking in what you think is normal day-to-day activity.
I mean, when Homeland Security is put on notice when you pay a credit-card off (Thanks DanAtNR) -- language like this in an immigration bill starts to take a little different appearance.