You’re definitely in the right direction with your thinking, and I want to encourage you to continue. It’s an honour to talk to you! Blindness is not one of the things mentioned within Leviticus. The things that are mentioned in Leviticus are: leprosy, childbirth, menstruation, sexual intercourse, nocturnal emissions, touching a dead body, and maybe one or two others that I’m forgetting at the moment. These were purely penitential symbolic liturgical laws for the Temple or desert Tent, given by God, SPECIFICALLY BECAUSE OF the Golden Calf incident, to wean the people, believe it or not, from idolatry, which is the worship of “dead things.” Idolatry involved conjuring up a dead spirit into an item of worship (in reality these spirits were demons). Idolatry leads the people to “blindness” of the true God…the worshippers of idols become “dead” like the spirits-in-items that they worship (puffed up in pride, blind and deaf to the truth, and even demonically possessed). The idea in the Leviticus passages is that leprosy, childbirth, menstruation, etc, all involve a symbolic form of “death” (the soul is in the blood when it is shed in menstruation or childbirth, leprosy is a living form of decomposition and being cut off or “dead” to the worship community for its own safety, nocturnal emissions are “fruitlessness” in regards to procreation…the ancients believed that children were already within the father and the mother just continued the “building up” of the child…how much loss of life, then, was involved in even a fruitful act of sexual intercourse, etc). The idea is this: don’t bring your uncleanness (death), a symbolic association to idolatry, into the liturgical Temple where the Living God dwells! It reinforced the message that they were to shun idolatry.
That being said, however, there was a later Jewish Tradition (probably Pharisaical…the Essenes were more obsessed with dogs not being allowed within the Temple!) from around the first century BC, wherein it was argued that the blind and the lame are not to be given entrance into the Temple. The reason for this lies behind a legalistic interpretation of a passage from either the Books of Kings or Chronicles where, when King David was conquering Jerusalem, the hostile inhabitants therein mocked him by saying that he was so weak that the blind and the lame would keep him out. Blindness, therefore, was not considered symbolically unclean by the Scriptures but only by the tradition of the Pharisees. The blind would, therefore, need no inspection and penitential ritual cleansing, which the priests, and not the Pharisees, would perform. Such “proofs” were given to the priests in order to demonstrate that God, and God alone, had done the impossible (especially in the healing of leprosy).
Interestingly enough, while this passage does not take place in Jerusalem, or anywhere even near it, it does use “house” imagery, which alludes to the Temple (“when he entered the house”). I think it is making a veiled reference to Jesus being the true High Priest within the True House, not made with hands, the Holy Spirit. Also, this passage shows Jesus abrogating these unclean penitential laws…he touches a dead girl, allows himself to be touched by a woman with an emission of unclean blood, touches two blind men guilty of Pharisaic uncleaness, earlier in chapter 8, he touches a leper, and even wants to go into a gentile’s house (gentile houses were considered unclean because many gentiles performed abortions and buried their dead children underneath or near to their houses). Jesus himself is not rendered “unclean” because he remains the same after making others truly clean!