Shaykh Saalih al-Fowzaan said:
As for the one who claims that he loves the Messenger ﷺ, and then he does not follow him, or that he introduces an innovation and thinks that he loves the Messenger while he introduces an innovation, then he is lying in his love for the Messenger ﷺ.
Like those who claim they love him and revive [the celebration of] birthdays, [then] these birthdays are an innovation.
Celebrating the occasion of the birthday of the Messenger ﷺ – this is an innovation for which Allaah has not sent down [any] authority.
And He ﷺ said:«…upon you is my Sunnah, and the Sunnah of the Rightly Guided Successors after me [so] hold on to it, and bite on to that with the molar teeth, and beware of the newly invented matters, for indeed every newly invented matter is an innovation, and every innovation is misguidance.»
[And] He ﷺ [also] said:«Whoever introduces anything into this matter of ours that which is not from it, will have it rejected.»
…meaning it will be rejected from him, and Allaah (Subhaanahu wa Ta’aala) will not accept it.