Sayyiduna Abu Hurayrah (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "Every child is born upon the fitrah (natural disposition); his parents make him a Jew, a Christian or a Magian."
Imam al-Awza'i (may Allah have mercy on him) said: They cannot take him out of the knowledge of Allah, and to the knowledge of Allah they all return.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب اللقطة / 12145