The Prophet ﷺ sent an army under the command of Usama bin Zaid. When some people criticized his leadership, the Prophet ﷺ said, "If you are criticizing Usama's leadership, you used to criticize his father's leadership before. By Allah! He was worthy of leadership and was one of the dearest persons to me, and (now) this (i.e. Usama) is one of the dearest to me after him (i.e. Zaid). (Using translation from Bukhārī 3730)   

عُمَرَ ؓ يَقُولُ بَعَثَ رَسُولُ اللهِ ﷺ بَعْثًا وَأَمَّرَ عَلَيْهِمْ أُسَامَةَ بْنَ زَيْدٍ فَطَعَنَ النَّاسُ فِي إِمْرَتِهِ فَقَامَ رَسُولُ اللهِ ﷺ فَقَالَ إِنْ تَطْعَنُوا فِي إِمْرَتِهِ فَقَدْ كُنْتُمْ تَطْعَنُونَ فِي إِمْرَةِ أَبِيهِ مِنْ قَبْلُ وَايْمُ اللهِ إِنْ كَانَ لَخَلِيقًا لِلْإِمَارَةِ وَإِنْ كَانَ لَمِنْ أَحَبِّ النَّاسِ إِلِيَّ وَإِنَّ هَذَا مِنْ أَحَبِّ النَّاسِ إِلِيَّ بَعْدَهُ  

[Machine] "He said, the Messenger of Allah ﷺ said, Sulaiman ibn Dawud (peace be upon them) said, 'I will visit seventy women tonight, and each one will bring me a knight who fights in the cause of Allah.' His companion said to him, 'Say, 'If Allah wills,'' but he did not do so and did not say, 'If Allah wills.'' So he went around all of them, and none of them brought him anything except one woman who came with half of a man's body. And I swear by the soul of Muhammad in His hand, if he had said 'If Allah wills,' they would have all fought in the cause of Allah.'"  

أَنَّهُ قَالَ قَالَ رَسُولُ اللهِ ﷺ قَالَ سُلَيْمَانُ بْنُ دَاوُدَ عَلَيْهِمَا السَّلَامُ لَأَطُوفَنَّ اللَّيْلَةَ عَلَى سَبْعِينَ امْرَأَةً كُلُّ وَاحِدَةٍ تَأْتِي بِفَارِسٍ يُقَاتِلُ فِي سَبِيلِ اللهِ فَقَالَ لَهُ صَاحِبُهُ قُلْ إِنْ شَاءَ اللهُ فَلَمْ يَفْعَلْ وَلَمْ يَقُلْ إِنْ شَاءَ اللهُ فَطَافَ عَلَيْهِنَّ جَمِيعًا فَلَمْ تَحْمِلْ مِنْهُنَّ إِلَّا امْرَأَةٌ وَاحِدَةٌ جَاءَتْ بِشِقِّ رَجُلٍ وَايْمُ الَّذِي نَفْسُ مُحَمَّدٍ بِيَدِهِ لَوْ قَالَ إِنْ شَاءَ اللهُ لَجَاهَدُوا فِي سَبِيلِ اللهِ أَجْمَعُونَ