Next follows the Saman. Verily, breath is the Saman, for all these beings meet in breath. For him who knows this, all beings meet to procure his excellence; he obtains union and oneness with the Saman.

In plain words: Breath is the Saman, the sung chants, because all beings meet in breath. For one who knows this, all beings come together to help him do well, and he becomes one with the Saman.