[NVDave]

As if we were ever in doubt of the actions of the Catholic Church on this topic.

[Campion]

Archbishop Gregory isn't "the Catholic Church" all by himself. He makes policy for his own diocese, not for anyone outside it.

But -- as you probably know -- there's a longstanding tradition that arms are not to be carried in Christian churches. In fact, some medieval churches (in Norway, for example) have a kind of balcony or portico around the outside whose purpose was specifically for the men to stack their weapons before entering the sanctuary.

As a counterbalance, read this.