The importance of following the prophet in all matters

Umar ibn al-Khattab said: “You were the most humiliated people, and Allah magnified you by sending His messenger to you (peace and blessings of Allah be upon him). And in whatever ways, besides the way of His Messenger (peace and blessings of Allah be upon him), you strive to achieve greatness, Allah will humiliate you”.  al-Hakim 2/245.