Using Custom Taxonomy Term ID for Custom Field

Try this code this should work for you

 global $post;    // load all 'sermon_speaker' terms for the post    $terms = get_the_terms($post->ID, 'sermon_speaker');    // we will use the first term to load ACF data from    if( !empty($terms) )    {        $term = array_pop($terms);        $custom_field = get_field('sermon_speaker_image', $term );        // do something with $custom_field        //i.e. echo $custom_field;        //i.e. echo "<img src='$custom_field'/>";       ?><div class="sermon-speaker-image" style="background-image: url('<?php echo $custom_field; ?>');"></div><?    }

You can read more on the official documentation of Advanced custom fields

Two thoughts:

First One

<div class="sermon-speaker-image" style="background-image: url('<?php the_field( 'sermon_speaker_image', 'sermon_speaker_' ?> . <?php echo $term_id ?> ); ?>');"></div>

I use echo to actually display it.

Second One

This is my favorite and actually working one.You can use jQuery to set the attribute background-image where you want and append the value from the custom type.

$(document).ready(function() {     var new_link = $(".sermon-speaker-image").attr("background-image");        new_link = x.append('<?php echo $term_id; ?>','');     jQuery(".sermon-speaker-image").attr("background-image", new_link);}

Ofcourse you have to check that the (url=url+id) image actually exists.