Here’s what I did: I set the theme to Twenty Fifteen, disabled all plugins, and cleared my browser’s cache. The homepage still did not load. However, I noticed that some pages of my site were loading in using the Twenty Fifteen theme while others continued to use the Nimble theme even after switching. It’s been a long time since the theme was installed/updated and I have a feeling that the initial installation was either incorrect or it is wildly out of date. I’m going to try clearing and updating the theme.
Thank you for the help.