Silsilat al-Ahadith al-Sahihah

Sayyiduna Aswad bin Sari’ (may Allah be pleased with him) says: I came to the Messenger of Allah (peace and blessings be upon him) and fought in jihad with him. One day, I suddenly killed some of the prominent people (of the opposing army), and the Mujahideen also killed their children. When this news reached the Messenger of Allah (peace and blessings be upon him), he said: “What is wrong with the people that killing has exceeded its limits and even children have been slaughtered?” A man said: O Messenger of Allah! They are the children of the polytheists. The Prophet (peace and blessings be upon him) said: “Even the best and chosen among you are the children of polytheists.” Then he said: “Beware! Do not kill children. Beware! Do not kill children. Every human is born upon (Islamic) nature, until his tongue makes it clear, then his parents make him a Jew or a Christian.”