diff --git a/core/modules/node/lib/Drupal/node/Plugin/views/row/Rss.php b/core/modules/node/lib/Drupal/node/Plugin/views/row/Rss.php
index 6c34a4d..fbdbbf7 100644
--- a/core/modules/node/lib/Drupal/node/Plugin/views/row/Rss.php
+++ b/core/modules/node/lib/Drupal/node/Plugin/views/row/Rss.php
@@ -168,12 +168,13 @@ function render($row) {
     $item->link = $node->link;
     $item->elements = $node->rss_elements;
     $item->nid = $node->nid;
-
-    return theme($this->themeFunctions(), array(
-      'view' => $this->view,
-      'options' => $this->options,
-      'row' => $item
-    ));
+    $theme_function = array(
+      '#theme' => $this->themeFunctions(),
+      '#view' => $this->view,
+      '#options' => $this->options,
+      '#row' => $item,
+    );
+    return drupal_render($theme_function);
   }
 
 }
diff --git a/core/modules/node/node.admin.inc b/core/modules/node/node.admin.inc
index 69b6b0a..a62648b 100644
--- a/core/modules/node/node.admin.inc
+++ b/core/modules/node/node.admin.inc
@@ -395,7 +395,11 @@ function _node_mass_update_batch_finished($success, $results, $operations) {
   else {
     drupal_set_message(t('An error occurred and processing did not complete.'), 'error');
     $message = format_plural(count($results), '1 item successfully processed:', '@count items successfully processed:');
-    $message .= theme('item_list', array('items' => $results));
+    $item_list = array(
+      '#theme' => 'item_list',
+      '#items' => $results,
+    );
+    $message .= drupal_render($item_list);
     drupal_set_message($message);
   }
 }
@@ -537,12 +541,16 @@ function node_admin_nodes() {
   );
   foreach ($nodes as $node) {
     $l_options = $node->langcode != Language::LANGCODE_NOT_SPECIFIED && isset($languages[$node->langcode]) ? array('language' => $languages[$node->langcode]) : array();
+    $mark = array(
+      '#theme' => 'mark',
+      '#type' => node_mark($node->nid, $node->changed),
+    );
     $form['nodes'][$node->nid]['title'] = array(
       '#type' => 'link',
       '#title' => $node->label(),
       '#href' => 'node/' . $node->nid,
       '#options' => $l_options,
-      '#suffix' => ' ' . theme('mark', array('type' => node_mark($node->nid, $node->changed))),
+      '#suffix' => ' ' . drupal_render($mark),
     );
     $form['nodes'][$node->nid]['type'] = array(
       '#markup' => check_plain(node_get_type_label($node)),
diff --git a/core/modules/node/node.module b/core/modules/node/node.module
index 2cd835f..6e3af3a 100644
--- a/core/modules/node/node.module
+++ b/core/modules/node/node.module
@@ -1116,10 +1116,12 @@ function template_preprocess_node(&$variables) {
   $variables['date'] = format_date($node->created);
   // @todo Change 'name' to 'author' and also convert to a render array pending
   //   http://drupal.org/node/1941286.
-  $variables['name'] = theme('username', array(
-    'account' => $node,
-    'link_attributes' => array('rel' => 'author'),
-  ));
+  $username = array(
+    '#theme' => 'username',
+    '#account' => $node,
+    '#link_attributes' => array('rel' => 'author'),
+  );
+  $variables['name'] = drupal_render($username);
 
   $uri = $node->uri();
   $variables['node_url']  = url($uri['path'], $uri['options']);
@@ -1370,11 +1372,15 @@ function node_search_execute($keys = NULL, $conditions = NULL) {
 
     $language = language_load($item->langcode);
     $uri = $node->uri();
+    $username = array(
+      '#theme' => 'username',
+      '#account' => $node,
+    );
     $results[] = array(
       'link' => url($uri['path'], array_merge($uri['options'], array('absolute' => TRUE, 'language' => $language))),
       'type' => check_plain(node_get_type_label($node)),
       'title' => $node->label($item->langcode),
-      'user' => theme('username', array('account' => $node)),
+      'user' => drupal_render($username),
       'date' => $node->changed,
       'node' => $node,
       'extra' => $extra,
@@ -1500,7 +1506,12 @@ function theme_node_search_admin($variables) {
     $row[] = drupal_render($form['factors'][$key]);
     $rows[] = $row;
   }
-  $output .= theme('table', array('header' => $header, 'rows' => $rows));
+  $table = array(
+    '#theme' => 'table',
+    '#header' => $header,
+    '#rows' => $rows,
+  );
+  $output .= drupal_render($table);
 
   $output .= drupal_render_children($form);
   return $output;
@@ -1907,8 +1918,12 @@ function theme_node_recent_block($variables) {
   $l_options = array('query' => drupal_get_destination());
   foreach ($variables['nodes'] as $node) {
     $row = array();
+    $node_recent_content = array(
+      '#theme' => 'node_recent_content',
+      '#node' => $node,
+    );
     $row[] = array(
-      'data' => theme('node_recent_content', array('node' => $node)),
+      'data' => drupal_render($node_recent_content),
       'class' => 'title-author',
     );
     if (node_access('update', $node)) {
@@ -1927,9 +1942,18 @@ function theme_node_recent_block($variables) {
   }
 
   if ($rows) {
-    $output = theme('table', array('rows' => $rows));
+    $table = array(
+      '#theme' => 'table',
+      '#rows' => $rows,
+    );
+    $output = drupal_render($table);
     if (user_access('access content overview')) {
-      $output .= theme('more_link', array('url' => 'admin/content', 'title' => t('Show more content')));
+      $more_link = array(
+        '#theme' => 'more_link',
+        '#url' => 'admin/content',
+        '#title' => t('Show more content'),
+      );
+      $output .= drupal_render($more_link);
     }
   }
 
@@ -1950,9 +1974,17 @@ function theme_node_recent_content($variables) {
 
   $output = '<div class="node-title">';
   $output .= l($node->label(), 'node/' . $node->nid);
-  $output .= theme('mark', array('type' => node_mark($node->nid, $node->changed)));
+  $mark = array(
+    '#theme' => 'mark',
+    '#type' => node_mark($node->nid, $node->changed),
+  );
+  $output .= drupal_render($mark);
   $output .= '</div><div class="node-author">';
-  $output .= theme('username', array('account' => user_load($node->uid)));
+  $username = array(
+    '#theme' => 'username',
+    '#account' => user_load($node->uid),
+  );
+  $output .= drupal_render($username);
   $output .= '</div>';
 
   return $output;
diff --git a/core/modules/node/node.pages.inc b/core/modules/node/node.pages.inc
index 9aa4982..56b0e71 100644
--- a/core/modules/node/node.pages.inc
+++ b/core/modules/node/node.pages.inc
@@ -148,7 +148,11 @@ function node_preview(EntityInterface $node) {
     // Display a preview of the node.
     if (!form_get_errors()) {
       $node->in_preview = TRUE;
-      $output = theme('node_preview', array('node' => $node));
+      $node_preview = array(
+        '#theme' => 'node_preview',
+        '#node' => $node,
+      );
+      $output = drupal_render($node_preview);
       unset($node->in_preview);
     }
 
@@ -265,13 +269,21 @@ function node_revision_overview($node) {
     $row = array();
     $type = $node->type;
     if ($revision->current_vid > 0) {
-      $row[] = array('data' => t('!date by !username', array('!date' => l(format_date($revision->revision_timestamp, 'short'), "node/$node->nid"), '!username' => theme('username', array('account' => $revision))))
+      $username = array(
+        '#theme' => 'username',
+        '#account' => $revision,
+      );
+      $row[] = array('data' => t('!date by !username', array('!date' => l(format_date($revision->revision_timestamp, 'short'), "node/$node->nid"), '!username' => drupal_render($username)))
                                . (($revision->log != '') ? '<p class="revision-log">' . filter_xss($revision->log) . '</p>' : ''),
                      'class' => array('revision-current'));
       $row[] = array('data' => drupal_placeholder(t('current revision')), 'class' => array('revision-current'));
     }
     else {
-      $row[] = t('!date by !username', array('!date' => l(format_date($revision->revision_timestamp, 'short'), "node/$node->nid/revisions/$revision->vid/view"), '!username' => theme('username', array('account' => $revision))))
+      $username = array(
+        '#theme' => 'username',
+        '#account' => $revision,
+      );
+      $row[] = t('!date by !username', array('!date' => l(format_date($revision->revision_timestamp, 'short'), "node/$node->nid/revisions/$revision->vid/view"), '!username' => drupal_render($username)))
                . (($revision->log != '') ? '<p class="revision-log">' . filter_xss($revision->log) . '</p>' : '');
       if ($revert_permission) {
         $links['revert'] = array(