141. Narrated Nu’am Al-Mujmir (radhi Allaahu anhu) : Once I went up the mosque, (along with) Aboo Huraira (radhi Allaahu anhu). (He performed ablution and) said, ” I heard the Prophet (Sallallaahu Alaihi Wasallam) saying,

‘On the Day of Resurrection, my followers will be called Al-Ghurr-ul-Muhajjaloon from the traces of ablution, and whoever can increase the area of his radiance(*) should do so (i.e. by performing ablution in the most perfect manner).'”

[Saheeh Al-Bukhaari, Hadeeth No. 138, Vol. 1]

(*) [H. 141] The Prophet (Sallallaahu Alaihi Wasallam) did not increase the area that what is washed of the bodyparts while doing the ablution as Allaah ordered to be washed, in the Qur’aan.
Source : The Book of At-Tahaara – Chapter 12 – It is preferable to increase the area of radiance and wash perfectly the body parts during ablution.
Al-Lulu Wal-Marjan,Compiled by : Fuwad Abdul-Baqi,Translated by : Dr. Muhammad Muhsin Khan

Notes:  al-Ghurr: beautiful, handsome   ;  al-Muhajjaloon (sing. muhajjal): bright, radiant.