These three varnas (Brahman, Kshatriya, Vaishya) and castes of either religious identity inside their respective Varna (Hindu Rājopādhyāya/Chatharīya/Pānchtharīya and Buddhist Vajrāchārya/Shākya/Urāy) collectively form the upper-caste "twice-born" segment of Newar society. 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. Srēṣṭha also maintain their superior status over others with the claim that they firmly belong to the mainstream Brahmanic Hindu cultural world than the Jyāpu and others, and are in much more intimate contact with the Brahmans. Because of their high social status, these upper-level castes have also traditionally formed the core of the land-owning gentry and as patrons to all other caste groups.