It's little more than "okay", even for an initial effort. Quite honestly, it's too simple (boring) to be very effective. I think the imagery on your site should establish and maintain a theme.
Assuming that the banner is the first thing your users look at, why not use a photo that describes what the site is about or one that invokes a favorable emotion?
Here's an example:
Here's another:
The Associated Gospel Churches of Canada
Check out these templates for some ideas:
Christian templates,church templates,religious templates,church website design
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