Shaykhul-Islaam Ibn Taymiyyah (May Allah have mercy upon him) mentioned:

Whenever the Muslims differ in a matter, returning it back to Allah and the Messenger is obligatory. Therefore whichever of the two statements the Book and the Sunnah prove, it’s obligatory to follow it.

(Majmoo’ al-Fataawaa, vol. 20, p. 10-12)

Translated by Abu Yusuf Khaleefah
18th of Safar, 1436 H (12-10-2015)
Masjid Nur Allah, Queens, NYC