We do not attempt here to present the legislative heritage left us by Imam ar-Ridha’ (a.s.) or trace the ahadith which were reported about him in this regard, for this is the job of authors of books of hadith and fiqh. What we would like to deal with here, rather, is to evaluate the knowledge which reached us from him and from other Imams of the Ahl al-Bayt (a.s.) in the area of legislation, and the safe route they took in providing us with a basis for deriving such legislative rules from their accurate source.
As we stated in the Introduction, what caused us to follow the creed of the Ahl al-Bayt (a.s.) and use their hadith as a source for legislation is due to the clear and unequivocal statements of the Prophet (S) regarding the necessity of upholding their way and following their guidance such as the tradition of the two weighty things (hadith al-thaqalayn) and of the ark of Noah (a.s.), and other ahadith which cannot be doubted in their authenticity, structure, or objective. This is why any hadith reported by Imam ar-Ridha’ (a.s.) or by any other Imam is regarded as though it had been said by the Prophet (S) not because these Imams have the authority to initiate legislation, or be independent in enjoying the responsibility of inventing a legislative rule, but by considering it an extension of the pristine legislation brought forth by the Prophet (S) from his Lord, due to what they learned of the secrets of legislation and its fruits left for them as a legacy by the Prophet (S), after being made by the Almighty as custodians of the Message after the Prophet (S).
The hadith narrated about them is, as is the case with the Holy Qur'an, both muhkam and mutashabih. The muhkam, as its name suggests, does not accept but one single meaning, while the mutashabih is on the contrary permitting many facets of interpretation, and its actual meaning is not known exactly. This is the meaning we accept for these two terms.
Imam ar-Ridha’ (a.s.) is quoted in a narration as having said, "Among our narratives are mutashabih like the Qur'an's, and also muhkam like the Qur'an's; so, seek help from the muhkam to understand the mutashabih, and do not follow the mutashabih without the muhkam else you should stray."
The Commander of the Faithful (a.s.) justifies the existence of Qur'anic verses which can be interpreted in more than one way by saying: "The Almighty has done so in order to foil the attempt of wrong-doers from among those who would take control over the legacy of the knowledge of the Book left by the Messenger of God (S), which he did not intend them to acquire, rendering them unable to explain the various possible meanings thereof." It is as if God willed that the Prophet (S) and those who would bear the Message after him would have a special distinction which is the understanding of what others are not able to understand so that people would resort to them when they are unable to understand certain verses of the Holy Qur'an which they need to understand for the betterment of their life and the comprehension of their creed.
As regarding the existence of the mutashabih in the hadith reported about the Ahl al-Bayt (a.s.), as the Imam pointed out in his tradition cited above, this can be justified in the following manner:
These Imams (a.s.) used to suffer a great deal of persecution at the hands of their contemporary rulers who incessantly pursued them and their followers, forcing upon them a very strict surveillance, counting their breath. In many cases, in the face of such an intolerable treatment at the hands of those rulers, the Imams had to resort to the taqiyya in many of their deeds and sayings. They might have been asked, for example, about their judgment of a particular incident, or about something related to the creed and school of thought, and they would answer in a way which permitted more than one way of understanding the answer due to their own apprehension of the ruler's watchdogs and informers.
The meaning may be derived at the time the question is put forth when a related matter is at hand. It will be built according to one of the possibilities inspired by the text which would provide the inquirer with the desired satisfaction of the answer while, at the same time, such possibilities are hidden from others who will be confused about them and about the actual meaning the Imam (a.s.) meant thereby. It is then that it must be compared with other ahadith said on similar occasions, or with the context of bases which agree with it and which were set by them, peace be upon them. The meaning of the mutashabih may be similar to the general and the particular, the unrestricted and the absolute, while the general and the absolute would then be similar to the mutashabih, the special and the restricted would be similar to the muhkam.
We cannot find in any other sect the genuineness which characterizes the creed of the Ahl al-Bayt (a.s.) in the area of legislation, for it relies on a deep understanding of the Holy Qur'an and the pristine Prophetic Sunnah which derives from its original leading fountainhead a source of its legislation and such rules.
For example, according to a narrative, a man asked Imam ar-Ridha’ (a.s.) about another man who said at the time of his death, "Any old slave I have is now emancipated for the sake of pleasing God." The Imam said, "Yes, there is a way to determine who is `old' according to the Almighty and Praised God Who says in His Book, `... till it became like an old date cluster;' therefore, anyone among his slaves who has been with him for at least six months must now be freed."
The date cluster becomes old and dry during the period of six months. In this example, the Imam (a.s.) did not contend himself by just providing a legislative rule; he also derives its rule from the text of the Holy Qur'an.
The Ahl al-Bayt (a.s.) did not sense the need to seek avenues which were distant from the legislative realities in the conclusions they reached such as qiyas (comparison), istihsan (preference), etc., which were regarded by others as indicative of the legislative rule when they lack a concrete text, due to the fact that, because of the knowledge and the secrets of the Message which they inherited from their grandfather the Messenger of God (S) as well as their own level of iman (firm belief), they were self sufficient, independent, and due to what God had endowed them with of the faculty of knowledge in order they might be His Proofs over people.
The Ahl al-Bayt (a.s.) strongly condemned the use of qiyas and other such methods invented by others as means whereby they would justify their derivations when they lacked concrete evidence. Because of this, many strong confrontations happened between them and these people, and we may discuss this subject in detail in our forthcoming book about Imam As-Sadiq (a.s.) because the most violent of such confrontations took place during his time when promoters of various sects were free to express their views.