All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
There is no doubt that whoever believes that what Allaah made lawful is forbidden, or makes permissible what Allaah forbade while knowing the religious ruling, then he has committed major Shirk [associating with Allaah]. Allaah Says (what means): {They have taken their scholars and monks as lords besides Allaah.}[Quran 9:31]. The Prophet interpreted the verse saying: "They made what Allaah has forbidden lawful to them, and considered it as lawful, and they forbade for them what Allaah has made lawful, this is how they worshipped them." [Al-Bayhaqi and At-Tabaraani]
Ibn Taymiyyah said: 'Many people love a caliph, a scholar, or an Ameer to the extent that they consider them as co-equals to Allaah, even if they say that they love them for Allaah's Sake. Whoever considers that other than the Prophet must be obeyed in everything which he orders or prohibits even if this is against the order of Allaah and His Messenger then he has considered this person as a co-equal to Allaah.' However, if a person did not act according to an authentic narration or a Quranic verse, he has not necessarily committed major disbelief. It might be that he misinterpreted the verse or did not understand its meaning, or that he imitated a Shaykh whom he trusted in regard to his religion and knowledge whereas he (the latter) does not know Allaah's Ruling and that of His Prophet regarding that particular narration or verse.
We have already issued Fataawa 82778, 84248 and 82570 on imitating the four schools, so please refer to them.
Allaah Knows best.