Sayyiduna Abd al-Rahman bin Ya'mar (may Allah be pleased with him) says: I was present with the Prophet (peace and blessings be upon him), and he (peace and blessings be upon him) was saying: "Hajj is nothing but Arafah. Whoever reaches the standing at Arafah before the dawn rises has attained the Hajj" or "his Hajj is complete. And the days of Mina are three; whoever hastens in two days, there is no sin upon him, and whoever delays, there is no sin upon him either."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 9812