You can control this with the Link List called "Alert Bar" (CONTENT > Link Lists > Alert Bar).

To turn it off, simply change the name of the Link List from "Alert Bar" to "Alert Bar Off". To turn it back on, change the name of the Link List back to "Alert Bar"

There are 4 elements of the alert bar. All of them can be edited by going to CONTENT > Link Lists > Alert Bar > Edit the 1 link within the link list

1: Icon - Editable with the "Icon Class" field. For a list of available icons, view this article of your setup guide.

2: Alert Name - This list editable with the "Name" field.

3: Alert Text - This is editable with the "Description" field.

4: Alert Link - The text will always say "Learn More" but what it can link to can be edited by updating the "Link" field. You can link to a page, sermon, event, article, etc from within your site or link out to an external website.