Umm Sulaym bint Milhan reported,

The Prophet ﷺ used to come to her home and take his afternoon nap there. She would spread out a leather mat for him to nap on, and since he sweated heavily, she would gather his sweat and mix it into perfume, storing it in small flasks.The Prophet ﷺ asked, "Umm Sulaym, what is this?"She replied, "It is your sweat, which I blend into my perfume."

Azami 9450

Sahih

عن أم سليم

أن النبي ﷺ كان يأتيها فيقيل عندها، فتبسط له نطعا فيقيل عليه، وكان كثير العرق، فكانت تجمع عرقه فتجعله في الطيب والقوارير، فقال النبي ﷺ: يا أم سليم ما هذا؟ قالت: عرقك أدوف به طيبي.

الأعظمي 9450صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Biography of the Prophet ﷺ
Chapter
Character of the Prophet ﷺ
Section
Whiteness of the armpits of the Prophet ﷺ
Numbering
Jami al-Kamil 9450 (2nd edition)
Azami 9450