The Holy Prophet (PBUH&HF) said;
Although thousands of prayers of the Prophets are accepted, they are also bestowed with one special prayer from Allah

that they may ask whatever they desire and it will certainly be granted. All the Prophets up to Prophet Eisa (A.S) have utilised their privileged prayers in this world

whereas I have saved it for the hereafter and that is my Intercession for my Ummah on the day of judgement.

My intercession is for all persons of my Ummah who have left this world with faith.
[In the narrations of Hadrat Abdullah ibn Abbas, Hadrat Abu Saeed Khudri and Hadrat Moosa Ashari, the same subject as mentioned as in the narrations of Ahmed, Bukhari & Muslim from Hadrat Anas. Bukhari & Muslim from Hadrat Abu Huraira]
Refrences:
1. Sahih Bukhari, Vol. 2, Page 932
2. Sahih Muslim, Vol. 1, Page 113
3. Musnad Ahmad, Vol. 3, Page 307
4. Musnad Ahmad, Vol. 3, Page 220
5.Sunan al-Kubra, Vol. 2, Page 433.