The Gemara in Massekhet Yoma (daf 57) relates that Rabbi Elazar, the son of the tanna Rabbi Yosei ben Ḥalafta, once testified that he saw the parokhet – the curtain that separated the Holy of Holies from the rest of the Temple – on a visit to Rome. The Gemara on today’s daf describes the background of that visit.
For the Roman government had once issued a decree that Jews might not keep the Sabbath, circumcise their children, and that they should have intercourse with menstruating women. Thereupon Rabbi Reuven son of Isterobeli cut his hair in the Roman fashion, and went and sat among them. He said to them:
If a man has an enemy, what does he wish him, to be poor or rich? They said: That he be poor. He said to them: If so, let them do no work on the Sabbath so that they grow poor. They said: ‘That is a good claim he said; let us nullify this decree.’ And they nullified it.
Then he continued: If one has an enemy, what does he wish him, to be weak or healthy? They answered: Weak. He said to them: Then let their children be circumcised at the age of eight days and they will be weak. They said: ‘That is a good claim he said; let us nullify this decree.’ And they nullified it.
Finally he said to them: If one has an enemy, what does he wish him, to multiply or to decrease? They said to him: That he decreases. If so, let them have no intercourse with their wives when they are menstruating. They said: ‘That is a good claim he said; let us nullify this decree.’ And they nullified it.
Later they came to know that he was a Jew, and the decrees were re-instituted. The Jews then conferred as to who should go to Rome to work for the annulment of the decrees. Let Rabbi Shimon ben Yoḥai go for he is experienced in miracles. And who should accompany him? — Rabbi Elazar the son of Rabbi Yosei.
Then ben Temalyon – a demon – came to meet them. He said: Is it your wish that I accompany you? Thereupon Rabbi Shimon wept and said: The handmaid of my ancestor’s house [Hagar] was found worthy of meeting an angel thrice, and I do not deserve assistance from an angel even one time. However, let the miracle be performed, no matter how. Thereupon the demon advanced and entered into the Emperor’s daughter and possessed her. When Rabbi Shimon arrived there, he called out: ‘Ben Temalyon emerge, ben Temalyon emerge’, and as he proclaimed this the demon left her.
The Emperor then said to them: Request whatever you desire. They were led into the treasury to take whatever they chose. They found the letter containing the decrees against the Jews, took it and tore it to pieces. It was with reference to this visit that Rabbi Elazar the son of Rabbi Yosei related: ‘I saw it (the parokhet) in the city of Rome and there were on it several drops of blood (from the bull and the goat of Yom Kippur).’