Thus they returned to their own country, and the Prince called together his boyars and the elders. Vladimir then announced the return the return of the envoys who had been sent out, and suggested that their report be heard. He thus commanded them to speak out before his retinue. The envoys reported, "When we journeyed among the Bulgars, we beheld how they worship in their temple, called a mosque, while they stand ungirt. The Bulgar bows, sits down, looks hither and thither like one possessed, and there is no happiness among them, but only sorrow and a dreadful stench. Their religion is not good. Then we went among the Germans, and saw them performing many ceremonies in their temples; but we beheld no glory there. Then we went to Greece, and the Greeks led us to the edifices where they worship their God, and we knew not whether we were in heaven or on earth. For on earth there is no such splendor or such beauty, and we are at a loss how to describe it. We only know that God dwells there among men, and their service is fairer than the ceremonies of other nations, for we cannot forget that beauty. Every man, after tasting something sweet, is afterward unwilling to accept that which is bitter, and therefore we cannot dwell longer here." Then the boyars spoke and said, "If there Greek faith were evil, it would not have been adopted by your grandmother Olga who was wiser than all other men." Vladimir then inquired where they should all accept baptism, and they replied that the decision rested with him.
+from The Russian Primary Chronicle, Laurentian Text, entry for the year 987AD.