In one of the talks it was mentioned that one loses precious energy when one develops negative emotions like anger and hatred. Is that true of sexual energy as well? Does one squander away precious spiritual energy anytime one gets sexual thoughts? Is that the reason brahmacharya is one of Patanjali’s yamas? What about entertainment, like watching TV, being on facebook, video games? Is that a waste of precious energy too?
As you say, with anger and hatred you lose “precious energy”, meaning you lose spiritual energy, elevated energy, inspired energy, soul-energy, energy of purity.
But you don’t lose quantity of energy, to the contrary: anger, Yogananda teaches, is one of the greatest stimulants of the will and that will produces great energy. Also people who hate can develop enormous energy. Likewise, sexual feelings and desires can push your energy high, to obtain what you want. Yogananda calls it “animal magnetism”, which can be quite strong. Simply it isn’t at all “precious energy”.
Concerning entertainment: it depends. There is both good and innocent entertainment and sensual, violent or dark entertainment, which pull the energy away from the “precious spiritual energy”. So chose well. Avoid TV as much as you can, it won’t have a good influence overall. Facebook, if you connect with nice people, is good, if you don’t become an addict. Video games: I don’t know much about them, but my guess is that basically they are a big waste of time and most of them pull our energy down: not good for your “precious spiritual energy”.
Yes, Patanjali’s yamas and niyamas are all attitudes which will elevate your consciousness and energy, taking you toward divine union (yoga), brahmacharya included.
All the best,