The Statement of Allah the Most High: ...And the Messenger (Muḥammad pbuh) was in your rear calling you back... (V3:153)

Hadith Number 4561

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Narrated Al-Bara bin Azib

The Prophet (ﷺ) appointed `Abdullah bin Jubair as the commander of the infantry during the battle of Uhud. They returned defeated, and that is what is meant by:-- "And the Apostle was calling them back in the rear. None remained with the Prophet (ﷺ) then, but twelve men."