You object to his command and before this you objected to the command of his father (Zaid). By Allah, he was fit as the commander and he was one of the dearest of persons to me and after him, behold! this one (Usama) is one of the dearest of persons to me. (Using translation from Muslim 2426a)
أَنَّهُ سَمِعَ ابْنَ عُمَرَ يَقُولُ بَعَثَ رَسُولُ اللَّهِ ﷺ بَعْثًا وَأَمَّرَ عَلَيْهِمْ أُسَامَةَ بْنَ زَيْدٍ فَطَعَنَ بَعْضُ النَّاسِ فِي إِمْرَتِهِ فَقَامَ رَسُولُ اللَّهِ ﷺ فَقَالَ «إِنْ تَطْعَنُوا فِي إِمْرَتِهِ فَقَدْ كُنْتُمْ تَطْعَنُونَ فِي إِمْرَةِ أَبِيهِ مِنْ قَبْلُ وَأَيْمُ اللَّهِ إِنْ كَانَ خَلِيقًا لِلْإِمَارَةِ وَإِنْ كَانَ لَمِنْ أَحَبِّ النَّاسِ إِلَيَّ وَإِنَّ هَذَا لَمِنْ أَحَبِّ النَّاسِ إِلَيَّ بَعْدَهُ»