It is narrated from Sayyiduna Zayd bin Thabit (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) used to offer (the Zuhr prayer) at midday. This was very burdensome for his Companions (may Allah be pleased with them). Then this verse was revealed: "Guard the prayers, especially the middle prayer, and stand before Allah in devout obedience." [Surah al-Baqarah: 238] (Sayyiduna Zayd bin Thabit (may Allah be pleased with him)) said: This is the middle prayer, because there are two prayers before it and two prayers after it.
In another narration the wording is that "he used to offer the Zuhr prayer at midday."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2154
(a) It is narrated from Zuhrah: We were sitting with Zayd bin Thabit (may Allah be pleased with him). They sent some people to Usamah bin Zayd (may Allah be pleased with him), and they asked him about the middle prayer. He said: It is Zuhr; the Messenger of Allah (peace and blessings be upon him) used to offer it at midday (in the heat).
(b) In a narration transmitted through another chain there is this addition: "That is, Zayd (may Allah be pleased with him) said: It is the Zuhr prayer," and then they sent this message to Usamah (may Allah be pleased with him).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2155
Sa'id bin al-Musayyab (may Allah have mercy on him) said: I, Urwah bin al-Zubayr (may Allah have mercy on him) and Ibrahim bin Talhah (may Allah have mercy on him) were sitting together. I said that Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) used to say that the middle prayer means the Zuhr prayer. He then said: Sayyiduna Ibn Umar (may Allah be pleased with him) passed by us, and Urwah (may Allah have mercy on him) said: Send someone to Sayyiduna Ibn Umar (may Allah be pleased with him) to ask him about this. So we sent a boy to him; he asked him, came back and said: It is the Zuhr prayer. We were not convinced by what the boy said, so we all got up and went to Sayyiduna Ibn Umar (may Allah be pleased with him) and asked him, and he said: It is the Zuhr prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2156
Hadith Gradingمحدثین:صحيح
Hadith Takhrij«صحيح۔ اخرجه ابن جرير في تفسيره 2/569»
Sayyiduna Ibn Umar (may Allah be pleased with him) narrates from Sayyiduna Zayd bin Thabit (may Allah be pleased with him) that he (may Allah be pleased with him) said: The middle prayer means the Zuhr prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2157
Hadith Gradingمحدثین:صحيح لغيره
Hadith Takhrij«صحيح لغيره۔ اخرجه ابن جرير في تفسيره 2/569»