Jami At Tirmidhi
643
Daif+2

Abdur-Rahman bin Mas'ud bin Niyar said:"Sahl bin Abi Hathmah came to a gathering of ours, and he narrated that the Messenger of Allah would say: "When you make an assessment, then take it and leave a third, if you do not leave a third, then leave a quarter

DaifAhmad Muhammad Shakir
DaifAl-Albani