How do we respond to the saying, "The lands of the East are the lands of prophets, and the lands of the West are the lands of saints"?

There is no evidence to suggest that the lands of the East are exclusively designated for prophets and the lands of the West for saints. All the prophets mentioned in the Quran are from the East, but this does not negate the existence of prophets who were not mentioned and who may have been from the West. As for the Friends of Allah (Awliya), they are present in every place and time. Their early masters were from the East, and sainthood (wilayah) is achieved by fulfilling its conditions, regardless of location.