DO I HAVE TO FOLLOW A CERTAIN MADHHAB?

Do I have to follow a certain School of Thought ? (meaning the four school of thoughts of Imam Abu Hanifah, the school of thought of Imam Malik ibn Anas, Imam Ash-Shafi'ee, and Imam Ahmad ibn Hambal)

First of all you should know that there were a lot of other Imams who existed during the times of these four Imams:

Imam Al-Awza'i (his school of thought was adopted in the greater Syria in Sham 200 years later after his death)

Imam Al-Layth ibn Sa'd (In Egypt - Imam Ash-Shafi'ee who said Imam al-Layth is more knowledgeable than Imam Malik)

Imam Sufyan al-Thawri (In Iraq - He was an expert scholar of Hadith)

Imam Al-Zuhd and many others...

But what really distinguished the four Imams (the fours schools of jurisprudence) from the rest of these other Imams is that they had what we know by "Ashab", students. Students who conveyed their teachings after their death. Their students recorded their religious rulings and they conveyed it to the people after them.

Now we go back to the question because this has to do in the depths of the area of: "Wa ašhadu anna Muhammadan Rasool Allah"

DO I HAVE TO FOLLOW A CERTAIN MADHHAB, A CERTAIN SCHOOL OF THOUGHT (even if it contradicts the Sunnah of Rasool Allah ﷺ) ?

The answer is NO. The only one you are suppose to follow is Rasool Allah ﷺ.

You are suppose to follow the HAQQ (the Truth) which the Messenger of Allah ﷺ brought in with the evidence (daleel).

But to be careful here , there are Muslims who are learned and are able to sort out the verses of the Qur'an and the hadith of the Prophet ﷺ, and they are able to filter out such as the abrogated, the general and particular, the explicit and implicit, the detailed, the clear and the ambiguous, this one is to be applied here, etc., what we know by the ijtihaad (the individual reasoning). Thus he is able to read the text of the Qur'an and Sunnah and simply deduce, understand it and implement it.

This one is unlawful for him to follow another person. They are to only follow the shari'ah evidence.

The one who is able to derive rulings from the Qur’an and Sunnah should take from them like those who came before him; it is not right for him to follow blindly (taqleed) when he believes that the truth lies elsewhere.

But then there are some Muslims who are not able to do that like you and I. There are some people who vary in their level of understanding and ability to derive rulings from the evidence. We have to be very careful here. They are not learned. They don't have the knowledge to grasp the evidence and sort it out, filtered it out through these two pure sources (Qur'an and Sunnah) and come out with a religious ruling, those could blindly follow a Scholar (who is upon the Qur'an and Sunnah upon the understanding of the Salaf), not necessary a madhaab, any Scholar (upon the Qur'an and Sunnah). Thus it is permissible for him to follow in matters in which he is unable to come to a conclusion based on the Qur’an and Sunnah and he needs guidelines concerning a particular issue.

What if you blindly following someone and then the evidence of Rasool Allah ﷺ came to you, the hadith, contradicting the madhaab or the school of thought, then you should abandon that and follow what came to you of clear evidence. You should not just stick to the madhaab only when you are able now to grasp, to understand, and implement the Sunnah of Rasool Allah ﷺ

وَمَ‍‌‍نْ يُشَاقِ‍‍‍قِ ‌ال‍‍رَّس‍‍ُ‍ولَ مِ‍‌‍نْ بَعْدِ‌ مَا‌ تَبَيَّنَ لَهُ ‌الْهُدَ‌ى‌ ‌وَيَتَّبِعْ غَ‍‍‍يْ‍‍رَ‌ سَب‍‍ِ‍ي‍‍لِ ‌الْمُؤْمِن‍‍ِ‍ي‍‍نَ نُوَلِّ‍‍هِ مَا‌ تَوَلَّى‌ ‌وَنُ‍‍صْ‍‍لِ‍‍هِ جَهَ‍‍نَّ‍‍مَ ۖ ‌وَس‍‍َ‍ا‌ءَتْ مَ‍‍صِ‍‍ي‍‍ر‌اً

"And whoever contradicts and opposes the Messenger (Muhammad ﷺ) after the right path has been shown clearly to him, and follows other than the believers' way. We shall keep him in the path he has chosen, and burn him in Hell - what an evil destination."

[Qur'an 4:115]

At the end of the day the methodology (manhaj) of the saved sect, what they do is that they follow the Consensus of the Scholars, the consensus of the madhahib. That's why you always find the jurist whom you asked questions regarding the matters of the Deen, they tell you: "the majority of the jurists they said this... Ahmad and Malik they said this ... but Imam Hanifa and others they said..." so we go with majority (consensus) provided that the majority have the strongest evidence .

Again we're after the authentic evidence (daleel) from the Qur'ān and Sunnah, you must provide the evidence.