The Caves of Turfan during the Tang Dynasty included materials of several religions. Christian, Buddhist, Manichean, and Zoroastrian texts were found in Cave 17 by A. Stein after he tricked a Taoist monk into letting him see them around 1901. It provided evidence of a vigorous intellectual climate and a mutual respect various religions had for each other. So it is no surprise to see monks of different faiths paired together in a mural of the Turfan region. In nearby Bezeklik we see a Buddhist monk with folded hands (on the right) greeting a monk with his hand in a mudra position. But what kind of monk is he. He is clearly not Chinese. He has blue eyes and Turkic facial features. Tocharians had adopted a blend of Christianity and Buddhism in a form created by Mani as early as the 3rd century. By the time we come to the period of the Tang Dynasty Manichean religion had virtually vanished. It existed only in the remote areas on the periphery of the Silk Road. We see in this mural two monks clearly distinct in culture and religion. The monk on the right has his right hand formed in a raised mudra. The tips of the forefinger and the thumb are touching forming a circle. The other three fingers are pointing upward which may have symbolized the Trinity.
In western iconography the hand gesture always symbolizes a theology either about the Trinity or the nature of Christ.