مُسْنَدُ أَحْمَدَ
Musnad Ahmad 4172
Musnad of Abdullah bin Mas'ood
It was narrated from ‘Abdullah, from the Prophet (ﷺ) that He said: “The first matter concerning which judgement will be passed among the people is bloodshed.”
Musnad Ahmad 4200Its isnad is saheeh, Muslim (1678)]