Allah has given every single Prophet, one request – one supplication that is guaranteed to be accepted. The Prophets of the past have used this to ask something that they really wanted to see fulfilled. Some prophets used this against their own people because they used to get so frustrated. For example, Noah after preaching for nine hundred and fifty years, got frustrated at his people for still not listening to his message and made this supplication:

O Allah I don’t want you to leave one house of disbelievers on this earth.

Thereafter, Allah destroyed his city, which was all of humanity at that time.

Similarly Prophet Ibrahim made a supplication to Allah for Prophet Muhammad, asking for the messenger to come from his progeny. That is why Prophet Muhammad later said:

“I’m the Du’a of my father Ibrahim.”

Moses made supplication against Pharaoh: “O Allah do not guide this person.” That is exactly what happened, Pharaoh died as a disbeliever. Suleiman made supplication to Allah – “give me a dominion that you have given to no other human before me.” So Allah gave him power that no one had before him.

The Prophet Muhammad had the greatest of the supplications and what did he use it for? The Prophet said:

“Allah has given one Du’a to every single prophet and every single messenger, that he has guaranteed that he will respond to. And every single prophet has used up this Du’a for himself in this world, except for me. I have saved it and I have not used it and I will not use it in this life. I have kept it for my Ummah and I will use it for them on the day of judgment. And my Du’a will be, “O Allah, forgive my entire Ummah”.

This is the Du’a of the Prophet, “that anybody who believed in me, O Allah forgive him.” Allah will accept this.

So here we see, how the Prophet saved this one Du’a for us, that he could have used for himself. But he chose to make the sacrifice for his Ummah, this shows us the love that he had for all of us.

Source: http://lifeofprophet.com