Taqlid implies that one follows the rules laid down by a specific Islamic school of thought (madhab) entirely, regardless of whether one is aware of the evidences presented in favor of those rules or not. There are four schools of Islamic thought prevalent today. Each of them uses the Qur'an and Sunnah of the prophet Muhammad (pbuh) as the primary source for guidance but the interpretation of the sources varies from one school to another.
Unfortunately, people who lack the necessary knowledge do not have the ability to interpret the Qur'an and Sunnah on their own. From the arguments in favor of taqlid, this carries most weight. The scholars who founded and developed the schools of thought in Islam are historically regarded as one of the most competent with regards to inference of the sources of Islam. Practitioners of taqlid believe the following verse refers only to them:
"Ask those of knowledge if you do not know." (16:43)
Performers of taqlid believe that it is correct to follow a specific school of thought even if one is not aware of the evidence in the Qur'an and Sunnah that supports it (as stated in the definition of taqlid). This is due the level of trust that they have placed in the competence of the teachers of these madhabs. With reference to the statements of the great founders of these schools of thought, it is difficult to accept such a belief. In fact, it is against the teachings of the founders to preach their opinions without knowledge of their evidence (Qur'an and Sunnah). Imam Abu Hanifa is reported to have said:
"It is forbidden for anyone who does not know my proofs to make a ruling according to my statements, for verily we are only humans we may say something today and reject it tomorrow."
Also, though there is no doubt that the Qur'anic verse refers to the founders and many teachers of the four schools of thought, yet it does not exclude those scholars who did not limit themselves to the method of interpretation adopted specifically by one of the madhabs. Throughout history, there have been many Islamic scholars who at times followed the Hanafi madhab and at others, followed another school of thought based on their study of the sources of Islam. Imam Suyuti, was taught the Shafi' method but later, based on his study of evidence presented by other schools of thought, he changed some of his practices and beliefs. It is known that Imam Suyuti did not believe that for the Friday Prayer to be valid, there needs to be at least forty Muslims present as the followers of Imam Shafi' do. Imam Suyuti believed the required number to be just three.
The other reason that has compelled many towards taqlid is that if I begin to study a simple aspect of Islam such as the method of prayer and independently arrive to a conclusion about it, how confident will I be in that method of prayer when known Islamic scholars far more knowledgeable than myself differ with me? Would I rather not prefer to accept the possible mistake of a knowledgeable scholar that the possible correction that I have put forth?
Due to lack of skills with regards to interpretation, someone like myself is not in any position to interpret Islam independently. Still, that does not exclude me from exploring the interpretations of various scholars of Islam and their evidences from the Qur'an and Sunnah. This does not imply that I have a license to pick any decision made by any competent scholar. If that were the case, we would all take the easiest of the options. The goal is to adopt the decision that is supported by the most evidence. At the same time, we are not in any position to refute the decision made by scholars whose views we do not adopt. Such criticism can only be from competent scholars of which we are not. Our approach should be to explore the interpretations of scholars and not to arrive to our own conclusions. In fact, I was once taught the following supplication:
"Oh Allah, save me from the practice of my personal interpretation of the Qur'an."
The Qur'an and the Sunnah are the basis of Islamic practice. They are what we should use as the basis of our faith and not depend just on the decisions made by specific scholars blindly (without reference to the Qur'an and Sunnah).
May Allah always guide us closer to the truth.