var confirmLeave=false;

$(document).ready(function() {
  $('a').not('.popup,[target="_blank"]').click(function() {
    if(confirmLeave)
      return confirm('Are you sure you want to leave this page? Doing so will result in losing your current position in the sermon.');
  });
  
  $('form').submit(function() {
    if(confirmLeave)
      return confirm('Are you sure you want to leave this page? Doing so will result in losing your current position in the sermon.');
  });
  
  setTimeout('toggleConfirmLeave()',20000);
});

function toggleConfirmLeave() {
  confirmLeave=true;
}