sentences:  Their upper status is maintained by their exclusive entitlement to secret Tantric initiation rites ("āgama" and "diksha" rituals) which cannot be conducted on castes other than the three upper varnas.Along with this, their higher status also requires them to conduct additional life-cycle ("saṃskāra") ceremonies like the sacred-thread wearing ceremony "upanayana" (for Rājopādhyāyas and Chatharīyas) or the rites of "baréchyégu" or "āchāryabhisheka" (for Vajracharyas and Shakyas).Higher castes are supposed to be 'more pure' because they celebrate more ceremonies and observe more rites of purification and because events such as births and death defile them for longer periods of time than they do Jyāpu agriculturists and other service providers.