مِشْكَاةُ الْمَصَابِيحِ
Mishkat al-Masabih 3749
The Offices of Commander and Qadi
Provisions and Presents for Rulers - Section 2
وَعَنْ عُمَرَ رَضِيَ اللَّهُ عَنْهُ قَالَ: عَمِلْتُ عَلَى عَهْدِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فعملني. رَوَاهُ أَبُو دَاوُد
‘Umar said, “I held an administrative post in the time of God's Messenger, and he gave me payment for it." Abu Dawud transmitted it.
Mishkat al-Masabih, 3749صَحِيح (الألباني)