(1) The Book of Purification
كتاب الطهارة
(110) Chapter: The Jewelry Of Wudu'
(110) باب حِلْيَةِ الْوُضُوءِ
Sunan an-Nasa'i 149 
It was narrated that Abu Hazim said:
"I was behind Abu Hurairah when he performed Wudu' for Salah. He washed his hand up to the armpit, and I said: 'O Abu Hurairah! What is this Wudu'?' He said to me: 'O Banu Farrukh! You are here! If I had known that you were here I would not have performed Wudu' like this. I heard my close friend (i.e., the Prophet (ﷺ)) says: "The jewelry of the believer will reach as far as his Wudu reached."
أَخْبَرَنَا قُتَيْبَةُ، عَنْ خَلَفٍ، - وَهُوَ ابْنُ خَلِيفَةَ - عَنْ أَبِي مَالِكٍ الأَشْجَعِيِّ، عَنْ أَبِي حَازِمٍ، قَالَ كُنْتُ خَلْفَ أَبِي هُرَيْرَةَ وَهُوَ يَتَوَضَّأُ لِلصَّلاَةِ وَكَانَ يَغْسِلُ يَدَيْهِ حَتَّى يَبْلُغَ إِبْطَيْهِ فَقُلْتُ يَا أَبَا هُرَيْرَةَ مَا هَذَا الْوُضُوءُ فَقَالَ لِي يَا بَنِي فَرُّوخَ أَنْتُمْ هَا هُنَا لَوْ عَلِمْتُ أَنَّكُمْ هَا هُنَا مَا تَوَضَّأْتُ هَذَا الْوُضُوءَ سَمِعْتُ خَلِيلِي صلى الله عليه وسلم يَقُولُ ‏ "‏ تَبْلُغُ حِلْيَةُ الْمُؤْمِنِ حَيْثُ يَبْلُغُ الْوُضُوءُ ‏"‏ ‏.‏
Grade :  Sahih (Darussalam)
Reference : Sunan an-Nasa'i 149
In-book reference : Book 1, Hadith 150
English translation : Vol. 1, Book 1, Hadith 149