"The word brahmacharya is also understood broadly in yoga as "sexual continence," which can be understood as being applicable as appropriate in different contexts (e.g., marital fidelity, celibacy for spiritual aspirants etc.), in more extreme terms (complete celibacy) or in more specific terms in relation to preserving and sublimating male sexual energy rather than losing it through ejaculation.
In yoga, the term brahmacharya tends to take on a connotation of disciplining the use of and preserving sexual energy. Brahmacharya is discussed in Patanjali's Yoga Sutras as one of the 5 Yamas, the foundational commitments for the practice of yoga. According to the Yoga Sutras,
the end-result or fruit of Brahmacharya practiced to perfection is unbounded
Aparigraha -
"Non-Possessiveness, Non-Hoarding
Why should we not hoard material possesions? "
The above link has really good information about it.
In a nutshell it explains how if we dedicate ourselves to accumulate material possesions we can end up controlled by them. it gives a great explanation of the Gunas and the relations to the Rajas and Tamas.