My fiancee and I are not believers or members of any Christian church. Consequently, we are planning a civil wedding ceremony. That said, our parents and most of our guests are either Catholic or identify as Christian. To make our guests comfortable, we thought of inviting a Catholic priest or minister of some other Christian denomination to preach.
Google makes clear that Catholic priests aren't allowed to officiate at weddings where neither party is Catholic and the wedding takes place outside a Catholic church, and I expect most other churches follow similar restrictions.
What's less clear is whether a Christian minister is allowed to preach at a civil wedding. From what I understand, ministers are allowed to preach anywhere to anyone and have a Biblical mandate to do so when given the opportunity. So would a Christian minister be allowed to preach at a civil wedding if somebody else officiated?