Rav Sama the son of Rava was a seventh generation Babylonian Amora and a student of Rav Ashi. After the passing of Rav Ruchami, he replaced him as Rosh Yeshiva of Pumpadisa, a position once held by his father Rava.
Tztzis of Ravina
Rav Sama noticed how the hole holding the strings of Ravina's tzitzis had ripped, leaving the loop of the strings very close the edge of the garment. He asked him why he did not follow the ruling of Rabbi Yackov that one must keep the loop away from the edge at least the length of a large knot. Ravina responded that Rabbi Yackov's ruling only applied to the time of the Tzitiz's creation. However since his tzitz had been created properly and ripped only afterwords, this ruling did not apply. Rav Sama became embarrassed by his lack of knowledge and Rav Ashi comforted him saying each Sage from Eretz Yisroel like Ravina was equivalent to two sages from Bavel.
Kever Rav Sama
Rav Sama is buried in the cliffs outside Achbara in the ruins of Chakuv based on the testimony of Rabbi Chaim Vital in the name of the Arizal. He is buried in a cave along with Rabbi Zerika and Rav Rabbi Oshiya Zeira Dman Chevraya. In two nearby dug caves are the kivarim of Mar Ukva and Rabbi Levitas ish Yavneh.