四臂觀音「三怙主」是藏傳佛教最為重要的神靈組合，將原本屬於西方淨土的基層信仰與側重儀軌修習及教法師承的藏傳佛教義理融合在新的觀音圖式中；與此同時，漢地觀音地位升起進入華嚴系統成為釋迦三尊或華嚴三聖的主尊，並接受了二位原主神的須彌獅座，形成文殊-觀音-普賢的「三大士」，成為宋夏以後中土寺院佛教神系的統領。藏地三怙主借用四臂觀音眷屬獅吼觀音與三大士獅座觀音形貌的一致性，也部分進入漢地觀音三大士系統，替代大悲觀音或騎獅水月觀音，組成文殊-四臂觀音/獅吼觀音-普賢組合的漢藏融合的三大士新樣式。自十四世紀以後，六字真言專指或等同於四臂觀音，但脫離了與之相連的四臂觀音圖像以密咒真言形式成為藏傳佛教的象徵；觀音和四臂觀音進入三大士引導的華嚴華藏世界的轉輪藏與四臂觀音及六字真言勾連，六字大明咒進而進入華嚴輪藏系統，大約在十五世紀末以瑪尼輪形式傳入藏區，逐漸成為藏地民間最為重要的信仰。

The Three Protectors (Rigs gSum mGon Po, or San Huzhu), which includes Chaturbhuja Lokeshvara, is the most important trinity of bodhisattvas in the Tibetan Buddhism. This combination of deities integrates the basic faith which is originally associated with the Western Pure Land (Sukhavati), and the beliefs with focus on ritual practices, teachings, and lineage in the Tibetan doctrines, creating a new representation of Avalokiteshvara. Meanwhile, the position of Guanyin in the Han-Chinese Buddhism rises and enters the Huayan system, becoming the new principal deity of the three honored ones or the three Huayan saints. Guanyin accepts the lion throne of the two previous main deities, which develops the Three Great Sages (San Dashi) with Manjushri, Guanyin and Samantabhadra in the trinity. Guanyin has then become the leading deity for the Buddhist monasteries in the Central Plains of China since the Song and the Western Xia dynasty. Though the consistency in the appearances of Lokeshvara’s retinue, the Simhanada Avalokiteshvara (Avalokiteshvara of the Lion’s Roar) and the Guanyin of San Dashi who is seated on a lion mount, Tibetan San Huzhu is partially integrated into the system of Han Chinese San Dahsi. This results in that the Tibetan Avalokiteshvara, the Lokeshvara, replaces the Great Compassion Guanyin or the lion-riding Shuiyue Guanyin, forming a new style of San Dashi, the trinity of Han-Tibetan fusion: Manjushri, Lokeshvara/Simhanada and Samantabhadra. After the fourteenth century, the Six-Syllable Mantra specifically refers to Lokeshvara as an equivalent name. However, it is later detached from the connection to the image of Lokeshvara and becomes the symbolic secret mantra in Tibetan Buddhism. Besides, Guanyin and Lokeshvara acquires association with the wheel of dharma (Dharmachakra) in the San Dashi-centered Huayan world. And the mantra is subsequently adopted by the same Huayan realm. Roughly in the late fifteenth century, the mantra spreads out to the Tibetan region in the form of Mani wheel, and gradually becomes one of the most important local religious practices in Tibet. 

四臂觀音; 三怙主; 三大士; 轉輪藏; 轉經筒

Lokeshvara; Rigs gSum mGon Po; San Dashi; Dharmachakra; Mani wheel