Meetinghouse Firewalls only accept RJ-45 internet connections. In some cases, an internet service provider (ISP) modem presents only a USB or ExpressCard connection. This is especially common with ISPs.
Devices such as the CradlePoint CBA750B can convert USB or ExpressCard connections to RJ-45 so they can be used with the meetinghouse firewall. More information about the CBA750B can be found on its product page.
Note that some of the CBA750B models include an integrated modem, but there is also a less expensive model available without an integrated modem (no modem). The no modem option is recommended, especially in cases where you already have an ISP modem presenting a USB or ExpressCard connection. A list of supported wireless devices and services can be found on the product page.