신명기 17:9 해설: Rashi, Chizkuni, Ibn Ezra & Or HaChaim

הכהנים הלוים [AND THOU SHALT COME UNTO] THE PRIESTS THE LEVITES — i.e. unto the priests, who descend from of the tribe of Levi.

ובאת אל הכהן, “and you come to the priest, etc.” This verse is a clear example to the scoffers who question the teachings of the Sages. They maintain that the written Torah was to be interpreted literally and that there is no parallel oral Torah. If there were no such oral Torah, the most competent scholars of which reside in Jerusalem, what would be the point of travelling to Jerusalem for clarification?

I have already explained [commentary on Numbers 16: 1] concerning the Levite priests that there can be priests who are not of Levite extraction.

ואל השפט אשר יהיה בימים ההם [AND THOU SHALT COME UNTO THE PRIESTS …] AND UNTO THE JUDGE THAT SHALL BE IN THOSE DAYS — The last apparently redundant words suggest: and even though he is not as eminent as other judges that have been before him, you must obey him — you have none else but the judge that lives in your days (i.e. you are only concerned with him) (Rosh Hashanah 25b).