Wordpress showing image as thumbnail without using thumbnail

Question

I'm currently working with a wordpress theme, where the homepage is set to show all the latest posts. All my posts are showing thumbnails, even tho i dont set an featured image in my posts.

It takes the first image in my post, and use it for thumbnail, but i dont want it to do that. The thumbnail should only be shown when i set it as featured image in a post.

So my question is: How can i remove the function that automatically shows the first image as thumbnail, and make it use my featured image in my posts.

Link to my website: http://bruunoggejl.dk

Thank you!

Answer 1

Replace get_the_image function

get_the_image( array( 'meta_key' => ...

For the_post_thumbnail function:

the_post_thumbnail( $size, $attr );