Imamate is the Basis of Islam
In this connection Khwaja Nasiruddin does not put forward more than one sentence. Anyhow the basis of the explanation given by the Shi'ah scholars is the same. They first advance a historical argument and say if Imam Ali's Imamate is proved, that of the other Imams' can be based on the authority of a declaration made by the preceding Imam. The Shi'ah scholars say that they know that Islam is the final religion and that it would not be followed by any other religion.
It is the most comprehensive religion and a complete code of human life. Then they put a question and ask whether the account of the Holy Prophet's life shows that he got enough opportunity to impart all the teachings of Islam to the people in general. When we study Islamic history we find that during the 23 years of his Prophethood he did not get such an opportunity. Although he did not miss any chance which he could avail of and taught many things to the people, yet in view of his special circumstances and his preoccupations in Mecca and Medina, it is certain that a period of 23 years was not enough for him to pronounce all the laws of Islam to all the people.
At the same time it was also not possible for him to give in complete information about such a perfect religion. Therefore there must be one or more persons among the companions of the Holy Prophet who might have obtained complete knowledge of Islam from him and be in a position to explain the teachings of Islam after his demise exactly in the same manner as he himself would do, with the only difference that he received Divine revelation direct, whereas they were to acquire this knowledge through him.
The Shi'ah scholars say that the Sunnis do not acknowledge the existence of any person to whom all questions regarding Islam could be referred, which means that they regarded Islam as imperfect. That is the reason why they had to resort to the theory of analogy, which they have put forward because they say that in the case of the questions which have not been provided for in the Sunnah, they have no alternative but to compare one question with another and to depend on hypothetical similarities for the purpose of deducing rules of law. The Shi'ah naturally do not share such a view. Imam Ali in Nahjul-balagha has denounced such a view and so have all other Imams.
Imam Ali says: "Has Allah revealed an incomplete religion?" (Sermon 18).
Does it need private judgment to complete? All the Imams have emphatically said that there is no question of Islam being imperfect and incomplete, and therefore no rule of law can be based on a personal opinion, a private judgment or conjecture.
There is a chapter in al-Kafi which is entitled: "There is nothing Permitted or Forbidden that is not provided in the Qur'an or the Sunnah". At least the general principles covering every rule of law have been provided.
All that is to be done is to apply these principles to the particular cases. That is what is meant by Ijtihad from the Shi'ah point of view. In other words, there are an adequate number of general laws in Islam, and the mujtahid (jurist) has only to provide details in their light. In contrast the theory of analogy implies that the number of the general laws is inadequate and therefore rules of law must be deduced on a hypothetical basis.
The Shi'ah scholars say that both the Shi'ah and the Sunnis admit that during the 23 years of his Prophethood the Holy Prophet could not make known to the people all the rules of Islam even in a general manner. The Sunnis say that the Holy Prophet left the matter as it was and departed this life; But the Shi'ah hold that it was not so. In order to complete his mission he selected certain persons who were inviolable and made known all the truths of Islam to the first one of them, namely Imam Ali. All these persons were fully equipped and competent to answer any question put to them. Imam Ali often said that he would answer any question put to him regarding Islam.
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