Sayyiduna Abu al-Darda' (may Allah be pleased with him) narrates: On Friday, the Prophet (peace and blessings be upon him) was delivering the sermon, admonishing and exhorting us; then he recited a surah. Sayyiduna Abu al-Darda' nudged Sayyiduna Ubayy bin Ka'b (may Allah be pleased with him) and asked: "When was this surah revealed? I have only heard it just now." Sayyiduna Ubayy signalled to him to keep quiet. When the people had finished the prayer, Sayyiduna Ubayy said: "Your only share from this prayer of yours is your idle talk." Sayyiduna Abu al-Darda' told the Prophet (peace and blessings be upon him) what Sayyiduna Ubayy had said, and the Prophet (peace and blessings be upon him) said: "Ubayy spoke the truth."
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 3129