I finally accomplished this by doing the following:
<?php
if( $posts ):
foreach( $posts as $post): // variable must be called $post (IMPORTANT)
setup_postdata($post);
$seriesID = get_the_ID();
endforeach;
wp_reset_postdata(); // IMPORTANT - reset the $post object so the rest of the page works correctly
endif;
$sermons = new WP_Query(array(
'post_type' => 'sermon',
'meta_query' => array(
array(
'key' => 'series',
'value' => $seriesID,
'compare' => 'LIKE'
)
),
'order' => 'DESC'
));
?>
I’d love to know if there’s a better way, though!
