Wrong photo with wrong post when shared

Hello,

When I share a post the appropriate picture does not show up. And it’s changed numerous times. All my blog posts have pictures, but it seems to choose them at random when sharing. Please fix this as soon as possible. This is a serious problem that I’m hoping can be fixed quickly. My website address is http://www.appointedtime.org. Please let me know what can be done as soon as possible. I need to be able to share my posts appropriately, with the right picture.

Thank you!
Erin