How can i change the confirm page text in simplenews
A grep on the simplenews module shows the text is coming from simplenews.subscription.inc file from following code.

on around line #582

/**
 * Generate the confirm subscription form.
 *
 * @see simplenews_confirm_add_form_submit()
 */
function simplenews_confirm_add_form($form, &amp;$form_state, $mail, $newsletter) {
  $form = array();
  $form['question'] = array(
    '#markup' =&gt; '&lt;p&gt;' . t('Are you sure you want to add %user to the %newsletter mailing list?', array('%user' =&gt; simplenews_mask_mail($mail), '%newsletter' =&gt; _simplenews_newsletter_name($newsletter))) . "&lt;p&gt;\n",
  );
  $form['mail'] = array(
    '#type' =&gt; 'value',
    '#value' =&gt; $mail,
  );
  $form['newsletter'] = array(
    '#type' =&gt; 'value',
    '#value' =&gt; $newsletter,
  );

  return confirm_form($form, t('Confirm subscription'), '', t('You can always unsubscribe later.'), t('Subscribe'), t('Cancel')
  );
}


since it is a form, you can simply implement hook_form_alter() to override 'question' field markup from your custom module, something of following sort

function my_module_name_form_alter(&amp;$form, &amp;$form_state, $form_id) {
  if($form_id == 'simplenews_confirm_add_form') {
      $form['question'] = array(
       '#markup' =&gt; t('Your Custom Confirmation Message Here'),
      );
  }
}