I got the exact same error. Including line 1924, and it started on March 28 on nomadicdecorator.com. I’m using the Coraline theme and current version of WordPress.
My hosting provider said we need to call a developer. Or pay for more hosting resources.
Not sure if there’s a clue in that both our sites got the same error starting in recent weeks/days?
I have tried all advice found so far in these forums and other sites, and my site still gets 500 and 503 errors frequently. The site works occasionally. Do I post my issue in a separate thread?