It is narrated from Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) that he said: I heard the Messenger of Allah (peace and blessings be upon him) saying: "The difference between a man and his disbelief and polytheism is abandoning the prayer."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الاستسقاء / 6497