Bhagavad Gita, the sermon given by Lord Krishna in the battle of Mahabharata is the only scripture on mother earth following which human beings finally reached state of enlightenment followed by moksha salvation. The word shastra means scripture.
State of moksha salvation can never be reached indulging in religious practices (rituals) or any other religion other than Hinduism.
The precept of moksha salvation is explained in detail in Bhagavad Gita. Lord Krishna in Bhagavad Gita says initially we have to demolish our ego in totality. This is necessitated to hear dictates of Lord Krishna coming from within our heart. In presence of ego we could not hear voice of Lord Krishna coming from within our heart.
At any given moment of life only one can survive ego or voice of Lord Krishna.
Furthermore we need establishing total control over five senses and mind. For achieving this there were many requisites on path of pure spirituality all of which are detailed in Bhagavad Gita. One of the foremost is indulging in nishkama karma yoga, indulging in karma in a way that fruits of karma belonged to God Almighty all the time and we were always unattached to fruits of karma.
Understanding doctrine of karma is an absolute must if we are to succeed on path of spirituality.
Simultaneously we need to curtail our desires and wishes in stages. If we indulged in karma like a nishkama karma Yogi then it was not difficult establishing control over five senses and mind.
To activate our brain to 100% capacity we have to awaken our kundalini shakti fully, the coiled Serpentine energy lying dormant in base of spine. Unless we did this our progress on path of spirituality would be minimal. For this practice of absolute celibacy for a minimum period of 12 years in continuation is necessitated.
Absolute celibacy differs from celibacy (Brahmacharya Vrata). Stopping flow of negative thoughts to our brain in totality is what absolute celibacy all about. The moment we succeed doing this one immediately reaches stage of Nirvikalpa Samadhi (absolute nothingness) when not a single thought entered our brain uninvoked.
For reaching state of enlightenment, self realization, god realization 100% activation of brain is necessitated. When this happens, Sahasra Pushpa (thousand petalled Lotus) existing in our brain behind forehead opens fully. One finally gains enlightenment followed by moksha salvation.
State of moksha salvation is reached when an enlightened one leaves mortal frame forever.