In the Name of Allah, most Compassionate, most Merciful

Quran 33:36. It is not for a believer, man or woman, when Allah and His Messenger have decreed a matter that they should have any opinion in their decision. And whoever disobeys Allah and His Messenger, he has indeed strayed in a plain error. 

Quran 8:20-22. O you who believe! Obey Allah and His Messenger, and turn not away from him while you are hearing. And be not like those who say: "We have heard," but they don't listen. Verily! The worst of living creatures with Allah are the deaf and the dumb, those who understand not.

Sahih Al-Bukhari Hadith 7.1 Narrated by Anas bin Malik
"...He who does not follow my tradition in religion, is not from me (not one of my followers)."

Sahih Al-Bukhari Hadith 9.384 Narrated by Abu Huraira
Allah's Apostle said, "All my followers will enter Paradise except those who refuse." They said, "O Allah's Apostle! Who will refuse?" He said, "Whoever obeys me will enter Paradise, and whoever disobeys me is the one who refuses."