It is not without reason or by chance that we worship towards the East. Since God is spiritual light, and Christ in the Scriptures is called the Sun of Righteousness and the Dayspring, the East is the direction that must be assigned to his worship. Moreover, the Scripture also says that God planted a garden eastward in Eden, and there He put the man and the woman whom he had formed, and when they had transgressed his command he expelled them and made them dwell over against the delights of Paradise, which clearly is the West. So then, we worship God seeking and striving after our old homeland. Moreover, Christ, when he hung on the cross, had his face turned towards the West, and so we worship, striving after him. And when he was received again into Heaven he was borne towards the East, and thus his apostles worship him, and thus he will come again in the way in which they beheld him going towards Heaven. So then, in expectation of his coming we worship towards the East. But this tradition of the apostles is unwritten. For much that has been handed down to us by tradition is unwritten.

—John of Damascus (ca. 760), The Fount of Knowledge 3, On the Orthodox Faith 4