Desiring to be teachers of the law; understanding neither what they say, nor whereof they affirm. (1 Timothy 1:7)
These guys wanted to be recognized as authorities of the law. They would have used a classic Jewish hermeneutic to interpret the law.
But they didn’t understand the true purpose of the law despite all of their observations and opinions.
They desired to place those who were freed of the law by grace, back under the law.