Is obedience to Muhammad “alaihissalam” necessary?

Allâhu ta’âlâ declares in the Qur’ân al-kerîm, in the eightieth âyat of the Surât-un-Nisâ that obedience to Hadrat Muhammad is obedience to Him. Then, unless His Messenger is obeyed, He will not be obeyed. In order to make it known that this is absolutely certain and clear, He declared in an âyat-i-kerîma: “Of course, it is certainly so.” Thus He gave no opportunity for some people who cannot think properly to see these two orders as obediences different from each other. Again, stating dissatisfaction with those who look onthese two obediences as two different things, in the 150th and 151st ayâts of Sûra Nisâ of the Qur’ân al-kerîm, Allâhu ta’âlâ declares: “The disbelievers want to differentiate Allah’s commands from His Prophets’ commands. They say they believe in certain parts, but not in others. They want to establish a new path between belief and disbelief. All of them are disbelievers. For all of them we have prepared Hell with very bitter torments.”