The Prophet ﷺ would often ask his servant, "Do you need anything?" One day the servant said, "Messenger of Allah, I have a need."He asked, "What is your need?"The servant replied, "My need is that you intercede for me on the Day of Resurrection."The Prophet ﷺ asked, "Who guided you to this?"He answered, "My Lord."The Prophet ﷺ said, "If that is so, then help me by making frequent prostration."
كان النبي ﷺ مما يقول للخادم: ألك حاجة؟ قال: حتى كان ذات يوم، فقال: يا رسول الله حاجتي. قال: ما حاجتك؟ قال: حاجتي أن تشفع لي يوم القيامة. قال: ومن دلك على هذا؟ قال: ربي. قال: إما لا فأعني بكثرة السجود.
Ahmad narrated it (16076) from Affan, who said, Khalid, that is, Wasiti, narrated to us, he said, Amr bin Yahya Ansari narrated to us, from Ziyad bin Abu Ziyad, freedman of Banu Makhzum, from a servant of the Prophet ﷺ, and he mentioned it.Haythami said (2/249), "Ahmad narrated it, and its narrators are the narrators of the Sahih." I say, it is as he said, for its narrators are the narrators of the two Sahihs except for Ziyad bin Abu Ziyad, and the name of Abu Ziyad is Maysara, one of the narrators of Muslim. Its isnad is sahih.The unnamed servant in this hadith may well be Rabia bin Kaab himself, except that in the first hadith found in Muslim, he asked to accompany the Prophet ﷺ in Paradise, while in this hadith he asked that Allah free him from the Fire. Perhaps this was a different request, made after the Prophet ﷺ had answered his first request.As for his saying, "Well then" (with a kasrah on the hamzah and a shaddah on the mim, formed by assimilating the nun of the conditional "in" into the mim of the extra "ma"), the meaning is, do not abandon this need, but be a help to me in fulfilling it through abundant sujud. This is what Sindi explained.