How do I only show exerpts of posts in Search Results and Archive page

I have found lots of posts on how to do the opposite, but right now my archive page and search results show as full articles. How do I change it so that it only shows excerpts of the posts? My site is https://www.guitarforworship.com, my host is bluehost, and my theme is mystique.

Here is the code for my search results:

<?php
 /* Mystique/digitalnature */
 get_header();
?>
  <div id="main">
   <div id="main-inside" class="clear-block">
    <!-- primary content -->
    <div id="primary-content">
     <div class="blocks">
      <?php do_action('mystique_before_primary'); ?>
      <?php
       $searchquery = wp_specialchars(get_search_query(),1);
       if(($searchquery) && ($searchquery!=__('Search',"mystique"))):
         if (have_posts()): ?>
         <h1 class="title"><?php printf(__("Search results for %s","mystique"),'<span class="altText">'.$searchquery.'</span>'); ?></h1>
         <?php
          mystique_pagenavi();

          while (have_posts()):
           the_post();
           mystique_post();
          endwhile; ?>

         <!-- page navigation -->
         <div class="page-navigation clear-block">
          <?php mystique_pagenavi('alignright'); ?>
         </div>
         <!-- /page navigation -->

        <?php else: ?>
         <h1 class="title"><span class="error"><?php _e('Nothing found.','mystique'); ?></span> <?php _e('Try a different search?','mystique'); ?></h1>
         <?php mystique_search_form(); ?>
        <?php endif; ?>
      <?php else: ?>
  	    <h1 class="title"><?php _e('What do you wish to search for?','mystique'); ?></h1>
        <?php mystique_search_form(); ?>
      <?php endif; ?>
      <?php do_action('mystique_after_primary'); ?>
     </div>
   </div>
   <!-- /primary content -->

    <?php get_sidebar(); ?>

   </div>
  </div>

<!-- /main content -->

<?php get_footer(); ?>

and my archive page:

<?php
 /* Mystique/digitalnature */
 get_header();
?>

  <!-- main content: primary + sidebar(s) -->
  <div id="main">
   <div id="main-inside" class="clear-block">

    <!-- primary content -->
    <div id="primary-content">
     <div class="blocks">
      <?php do_action('mystique_before_primary'); ?>
      <?php
       if (have_posts()) :
        $post = $posts[0]; // Hack. Set $post so that the_date() works.
        $desc = category_description();

        if (is_category()): ?>
         <h1 class="title archive-category"><?php echo single_cat_title(); ?></h1>
         <?php if($desc): ?><div class="category-description"><?php echo $desc; ?></div><?php endif; ?>
       <?php elseif(is_tag()): ?>
         <h1 class="title archive-tag"><?php printf( __('Posts tagged %s', 'mystique'), '<span class="altText">'.single_cat_title('', false).'</span>'); ?></h1>
       <?php elseif (is_day()): ?>
         <h1 class="title archive-day"><?php printf(__('Archive for %s', 'mystique'), '<span class="altText">'.get_the_time(get_option('date_format')).'</span>');  ?></h1>
       <?php elseif (is_month()): ?>
         <h1 class="title archive-month"><?php printf(__('Archive for %s', 'mystique'), '<span class="altText">'.get_the_time(__('F, Y','mystique')).'</span>');  ?></h1>
       <?php elseif (is_year()): ?>
         <h1 class="title archive-year"><?php printf(__('Archive for year %s', 'mystique'), '<span class="altText">'.get_the_time(__('Y','mystique')).'</span>');  ?></h1>
       <?php elseif (is_author()): ?>
         <h1 class="title archive-author"><?php _e('Author archive','mystique'); ?></h1>
       <?php elseif (isset($_GET['paged']) && !empty($_GET['paged'])): ?>
         <h1 class="title"><?php _e('Blog Archives','mystique'); ?></h1>
       <?php endif; ?>
       <div class="divider"></div>

       <?php
        while (have_posts()):
         the_post();
         mystique_post();
        endwhile;

        mystique_pagenavi();

       else:

         if (is_category()): ?> <h1 class="title"> <?php printf(__("Sorry, but there aren't any posts in the %s category yet.", "mystique"),single_cat_title('',false)); ?> </h1> <?php
         elseif (is_date()): ?> <h1 class="title"> <?php _e("Sorry, but there aren't any posts within this date."); ?> </h1> <?php
         elseif (is_author()):
          $userdata = get_userdatabylogin(get_query_var('author_name')); ?>
          <h1 class="title"> <?php printf(__("Sorry, but there aren't any posts by %s yet.", "mystique"),$userdata->display_name); ?> </h1> <?php
         else: ?> <h1 class="title"> <?php _e('No posts found.'); ?> </h1> <?php  endif;

       endif;
       ?>
       <?php do_action('mystique_after_primary'); ?>
     </div>
    </div>
    <!-- /primary content -->

    <?php get_sidebar(); ?>

   </div>
  </div>
  <!-- /main content -->

<?php get_footer(); ?>

I’m kind of new to all this, so thanks so much for your help!

Jamianne