Muhammad bin al-Ash'ath said: I visited Sayyidah Aishah (may Allah be pleased with her), and she said to me: Once I was sitting with the Messenger of Allah (peace and blessings be upon him) when three Jews came. One of them asked permission (to enter). Then she mentioned the complete hadith. In it is that he (peace and blessings be upon him) said (to Aishah (may Allah be pleased with her)): "Do you know over what things the Jews envy us?" (She said:) I said: "Allah and His Messenger know best." He (peace and blessings be upon him) said: "They envy us over the qiblah to which we were guided while they strayed from it, and they envy us over Friday (Jumu'ah), to which we were guided while they turned away from it, and the third thing: they also envy us over our saying Amin behind the imam."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2442