How are the cabinets arranged? If the eight speakers are distributed, say four down each side of the space or similar, then you may have some level adjustments delay or other processing that relate to specific boxes rather than to all of the speakers. Maybe that is handled by the two channels addressing two 'zones' of speakers, but you probably want to be sure that you are not limiting yourself by paralleling four speakers on each channel.
A good example here of looking at the details in that while the EV Sx80 is a nominal 8 Ohm impedance, it is less than 8 Ohms between roughly 170Hz and 250Hz, being 7.2 Ohms at around 200Hz, while it is greater than 8 Ohms at other frequencies, in fact up around 3kHz the impedance is over 150 Ohms.
At the same time, the QSC RMX1450 shows only an EIA 1kHz, 1% THD rating at 2 Ohms, it does not show a 2 Ohm FTC 20Hz to 20kHz, 0.1% THD rating as it does for 4 and 8 Ohm loads.
This combination of the speaker impedance and amp rating details indicates that you could potentially be pushing the amp very hard. However, given the Catholic church, speech only application you may be just fine.