$customTaxonomyTerms = wp_get_object_terms( $post->ID, 'CUSTOM_TAXONOMY', array('fields' => 'ids') );
$args = array(
'post_type' => 'POST_TYPE',
'posts_per_page' => 3,
'order' => 'DESC',
'orderby' => 'meta_value',
'tax_query' => array(
array(
'taxonomy' => 'CUSTOM_TAXONOMY',
'field' => 'id',
'terms' => $customTaxonomyTerms
)
),
'post__not_in' => array ($post->ID),
);