Unable to remove jquery from header and put in before body ends

jQuery is built into WordPress, so if any other enqueued script relies on it, it’s automatically loaded.

To move it to the footer, you have to reregister it, like this:

function my_footer_jquery () {
    wp_deregister_script ('jquery');
    wp_register_script ('jquery', includes_url ('/js/jquery/jquery.js'), array (), NULL, true);
    wp_enqueue_script ('jquery');
}
add_action ('wp_enqueue_scripts', 'my_footer_jquery');