Sayyiduna al-Bara' (may Allah be pleased with him) said: A man came to the Prophet (peace and blessings be upon him) and said: "I bear witness that there is no god but Allah and that you are His servant and Messenger." Then he fought on the battlefield of jihad until he was martyred, and the Prophet (peace and blessings be upon him) said: "He did little, but he gained much reward."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18541
Sayyiduna al-Bara' (may Allah be pleased with him) said: A man covered in iron came to the Messenger of Allah (peace and blessings be upon him) and said: Shall I fight, or accept Islam? He (peace and blessings be upon him) said: "First accept Islam, then fight." So he accepted Islam, then fought and was martyred. He (peace and blessings be upon him) said: "The deed is little, and the reward given is much."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18542
Sayyiduna Abu Hurayrah (may Allah be pleased with him) said: Amr bin Uqaysh had usury (riba) owed to him from the time of Ignorance, and because of the usury alone he could not accept Islam. On the day of Uhud he came and said: Where is my cousin? They said: At Uhud. Then he asked: Where is so-and-so? They said: He too is at Uhud. He asked again: Where is so-and-so? They said: He too is at the battle of Uhud. He put on his armour, mounted his horse and headed towards them. When the Muslims saw him, they said: O Amr (may Allah be pleased with him), keep away from us. He said: I have accepted Islam. Then he fought until he was wounded, and he was brought back in that wounded state. Sayyiduna Sa'd bin Mu'adh (may Allah be pleased with him) said to his sister: Ask him whether he fought out of tribal pride and anger on their behalf, or for Allah and His Messenger (peace and blessings be upon him)? He said: No, rather for Allah and His Messenger (peace and blessings be upon him). He died and entered Paradise, and he had not prayed a single prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18543