On the basis of 2 noble truths of Samvrti-satya and Paramārtha-satya,Hīnayāna developed a double-bodies theory with Rūpakāya(form body)and Dharmakāya (truth body), which is in duality and conflict of true and false. It’s criticized as partially empty and self-salvation by Mahāyāna, even Dharmakāya in Hīnayāna refers to supreme attainment and ideal of transcendence. Mahāyāna carries on its spirit of “dvi artha” accomplishments of self and others, unification of wisdom and compassion, rescue all sentient beings with skillful means without any attachment in mind. Since all beings (including Buddha and other 9 realms) are equally with innate Buddha-nature and sharing the same resultant truth body (Dharmakāya), “body” could be different from views of transitory collection, a burden with clinging or accomplishment of means with liberating. Mahāyāna created their theories of Buddha-bodies in more harmonious and perfect ways relative to double-bodies theory from Hīnayāna. Avalokiteśvara attained Buddhahood in the past life, completely and perfectly enlightened with respect to pañca-jñānāni (5 wisdoms) and trikāya (3 bodies of Buddha), the omnipresent Dharmakāya (truth body), the solemn Sambhogakāya (complete enjoyment body) and the expedient Nirmānakāya (emanation body). For totally realized the impermanence of life and the faults of cyclic existence, Avalokiteśvara vowed to come back the world for saving other beings with completely pervaded by heartwarming love and compassion, by skillfully teaching the paths of deliverance with kāyakarmaṃ (physical actions), vākkarmaṃ (verbal actions) and manokarmaṃ (mental actions) according to dependent-arising, in order to enlighten others’ recognizing the Buddha-nature and starting Buddhist practice. The Buddha-nature is a key between the theory of Buddha-bodies as correct views of completely enlightened and the emanations of Avalokiteśvara as model teaching of attaining full enlightenment. Attainment depends upon it, rescue others is the function of it, and compassion comes from the sympathy of “every sentient being has Buddha-nature”. Therefore, the profound wisdom of Buddha-bodies, the magical powers of Bodhisattva, dvi artha and ṣaḍ-pāramitā (six perfections), these theories of dharma are all about self-cultivation. Instead of looking for the external Buddha and Avalokiteśvara, why not just return to our true-nature which is equal with Buddha? The unique present of Dharmakāya is our wisdom truth body, and the ever-changing Sambhogakāya and Nirmānakāya are our flexible applications. Meditating in the life practice and being primordially pure, every one could be the fully enlightened one.