Juergen chants the mantra Namah Shivaya Namah Shivaya. "Namah" means prostration. "Namah Shivaya" means "the prostration before Shiva". You can find this kirtan in the Yoga Vidya Kirtan Songbook as No. 2.
Come along to sing this bhajan "Namah Shivaya Namah Shivaya". You listen in this podcast a live-recording from the Yoga Vidya Ashram in Bad Meinberg, Germany.