The words of yat pinde tat brahmande can be taken on a physical level as they remind the yogi that their physical body is made of the same substance as the world around them. It can also be taken spiritually to mean that their consciousness, or inner life, is indistinguishable from that outside of them.
Yogis believe that it is mala, or impurity, that builds walls between the individual self and the truth of oneness with the universal Self. Through yogic practices and progress on the spiritual path, these walls can be removed. The meaning of yat pinde tat brahmande implies that all separation is a construct and an illusion. Through yogic practices, yogis try to break through the illusion of separation and become Self-realized, experiencing the truth of yat pinde tat brahmande.
Yat pinde tat brahmande can be chanted repeatedly as a mantra, in the practice of japa. Some say this can help pierce the chakras, allowing for accelerated spiritual development.