I used to spend my night in the company of Messenger of Allah (ﷺ) and used to put up water for his ablutions. One day he said to me, "Ask something of me." I said: "I request for your companionship in Jannah". He inquired, "Is there anything else?" I said, "That is all." He said, "Then help me in your request by multiplying your prostrations".

[Muslim].