Sayyiduna Rafi' bin Khadij (may Allah be pleased with him) narrates: I and al-Khatmi came to the Prophet (peace and blessings be upon him) when he (peace and blessings be upon him) intended (to set out for) Badr. I said: O Messenger of Allah, I want to go out with you too. He (peace and blessings be upon him) began to draw back his hand and say: "I consider you too young, and I do not know what you would do if you met the enemy." I said: Do you know that I can shoot back at whoever shoots (an arrow)? But he (peace and blessings be upon him) sent me back, so I could not take part in Badr.
Hadith Referenceالمعجم الكبير للطبراني / باب الراء / 4402