Narrated by Sayyiduna Bara bin Azib (may Allah be pleased with him):
A man came to the Prophet (peace and blessings of Allah be upon him) equipped with weapons and said, "O Messenger of Allah! Should I go for jihad or (first) accept Islam?" The Prophet (peace be upon him) said, "First accept Islam, then go for jihad." So he did so, and (in jihad) he was martyred. The Messenger of Allah (peace be upon him) said: "He did very little work but will receive a great reward."