When the Messenger of Allah ﷺ appointed Usama as commander, word reached him that people were criticizing Usama and questioning his command. So he stood up, as Salim related to me, and said, "You criticize Usama and question his command, just as you did with his father before him. By Allah, his father was truly worthy of command and was the dearest of all people to me, and this son of his after him is among the dearest of people to me. So I urge you to treat him well, for he is among the best of you."
حدثنا يحيى بن آدم حدثنا زهير عن موسى بن عقبة عن سالم بن عبد الله بن عمر
أن رسول الله ﷺ حين أمر أسامة بلغه أن الناس يعيبون أسامة ويطعنون في إمارته فقام كما حدثني سالم فقال إنكم تعيبون أسامة وتطعنون في إمارته وقد فعلتم ذلك في أبيه من قبل وإن كان لخليقا للإمارة وإن كان لأحب الناس كلهم إلي وإن ابنه هذا بعده من أحب الناس إلي فاستوصوا به خيرا فإنه من خياركم
Its isnad is sahih. Something similar to it has already appeared in an abbreviated form through the narration of Abdullah bin Dinar from Ibn Umar (4701), where we quoted from Tarikh Ibn Kathir that Bukhari also narrated it through the route of Musa bin Uqba, from Salim, from Ibn Umar. So here is the route of Musa bin Uqba in the Musnad as well. And it is indeed fitting, as noted in the margin of manuscript M, and it is indeed fitting.