Changing configurations for Jrnl
It looks like you're attempting to execute the .jrnl_config file. You don't want to execute it, you want to edit it. i.e. nano ~/.jrnl_config or open ~/.jrnl_config.

In the error message, Bash is telling you that you don't have permission to execute the file. This is because execute permission isn't given to your user (or any user, most likely) for that file. This makes sense because the file isn't meant to be executed--it's a configuration file.