Gate Gate Paragate...

If you attend evening prayer sessions at a Vietnamese Buddhist temple, one of the scriptures that you will hear chanted is the Heart Sutra.
This is the most concise sutra in the Mahayana canon, and is particularly prized in the Zen school of Buddhism. Though short, it is densely and enigmatically phrased, and a practitioner could easily spend a lifetime devoted to its study. Some do.
One of the moments I love during chanting is when we reach the end of the sutra and the mantra is chanted. This is the famous mantra Gate Gate Paragate Parasamgate Bodhi Svaha. As the lay people sit cross-legged on the floor the mantra is chanted over and over at quite a dizzying pace, the fish drum beating the pace. It really is a transcendent moment.