Yes, a free wordpress site might work for your church website, the domain name is one that is fairly easy to remember because so many people have wordpress sites and "free" is a pretty good price.
But if you want any upgrades from their free package they are expensive (compared to “real” web site hosting).
Joomla is better...If you will do quite a few updates then that is a good way to go, but it is not easier to use than Joomla; I use Joomla instead of wordpress because Joomla is a lot more powerful. Either would work well for you if you don't need a lot of features and you don't ever need to do any customizing. If you want to do forms or want other features you will wish you chose Joomla. I have never found anything Joomla couldn't do.
A real domain name...If you want a domain name like pritchardwebpages.com you may want to consider buying a webhost. That will cost you about $120 a year (domain name and webhost). But if you are happy with something like pritchardwebpages.wordpress.com then you don’t need to buy anything.
Mobile ready...But when you are thinking over which type of website to get, and you look over the free wordpress templates, look for ones that say “responsive”. That is the current term for websites that rescale for any device.
I would highly encourage you to get a website that works on cell phones and tablets. Currently about 50% of internet use comes from non-desktop computers so you want to be sure your site will look good on all devices. That is easier said than done.