Sayyiduna Jundab (may Allah be pleased with him) relates: We were young, strong boys with the Prophet (peace and blessings be upon him). We learned faith before the Qur'an; then, when we learned the Qur'an, our faith increased through it. And today you learn the Qur'an before faith.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5292