By the end of the fourth century the educated bureaucratic class realized that the future lay with Christianity and that the best way to preserve what was good and true in Roman culture was to embrace the new religion. (firstthings.com)
Only at the end of the fourth century do we see anything like a face of Christ presented alone, without background details or other figures in a narrative composition. (religion-online.org)
By the end of the fourth century the western sources are more or less unanimous that Thomas worked in India. (religion-online.org)