Rabbi `Oḅadyah Maimūnī on Reason, Purity and the Mitzvōt

Were an individual to remain steadfast and persevere continuously until he achieved this state, then the phenomena that were previously concealed from him and others, would be revealed to him. Reason’s will shall strengthen and reveal that which is inscribed on the Tablet (al-lawḥ) Divine visions will be manifested to him without his knowing whence they came. He will walk by the light of his intellect, directed by its guidance. So take heed of your soul and safeguard its form, for the former has no lasting beatitude unless accompanied by Reason... [Like Moses taught the tribes] imparting to each individual in accordance with his capacity of understanding; this is similar to the manner in which reason itself proceeds [with us]. Chapter 6

Know that prolonged consumption of harmful foodstuffs causes acute ailments... Likewise a man who neglects his soul, abandoning it to its illness through his indulgence in worldly affairs, spending night and day buying and selling and so forth, will have nothing but fearful and alarming dreams upon retiring to sleep... It is for this reason that our pure and purifying Law has cautioned us concerning all external and internal defilement. The former, such as menstruation and nocturnal emission, are to be cleansed through immersion in a miqvah. Thus, Aaron and his descendants were enjoined “to wash their hands and feet, that they do not perish” (Ex. 30.21) this being the reason for the act of purification. For through the conviction man’s soul acquires after immersion that all veils, as it were, have been lifted, there ensues a state similar to spiritual predisposition (tahayyu’) and communion (ittiṣāl) with God. If not in need of immersion, then one must carry out the ablution of the hands and feet in order that the natural heat circulates in the body and arouse thereby the soul... “Say not v’neṭme’tem and (you shall become defiled) but v’niṭamṭem (and you shall become feeble-minded). (Yōmā’ 39a) Chapter 7.49-51, 53

In a similar spirit, other prohibitions have been instituted by the religious law in order to restrain man’s lust and keep him from resembling the beast. Among these rank the class of forbidden unions and those not legitimately contracted... Also belong to this group the precept of circumcision which is carried out on the physical organ through which marriage is consummated. As for the commandments concerning the wearing of tzītzīt and tefilīn and the fixing of an inscription to the mezūzah, they were instituted in order to remind the soul at the moments of inadvertence of its purpose and it is said concerning the tzītzīt, “That you may look upon it and remember all the mitzvōt of YHVH’. (Num. 15.39)... Hence it behooves the wise man not to ascend to a state which is too elevated for him but to be aware of the extent of his soul’s (capacity) and advance gradually, as is the wont of nature, which assimilates things progressively... be heedful of your soul, so that when you far upon the Path, you will be free of fear, “For the ground upon which you stand is holy” (Ex. 3.5) Mark these my words.” Chapter 5