1:5-7 For the goal of the commandment is love from a pure heart and a good conscience and a genuine faith, with regard to which some have turned aside and wandered into foolish talk, wanting to be teachers of the Law, but neither knowing what they are saying nor about what they have strongly maintained.
The vocabulary in these three verses is very unique for Paul's writings. Three of the words appear only in the pastoral epistles, and two appear nowhere in Paul's writings outside these verses.
The mention of a commandment begins to clarify for us the nature of the fables and genealogies, although not much. The false teachers at Ephesus want to teach the Jewish Law to the believers there, but they do not understand the proper goal of the commandments of the Law. The purpose of the Law is for people to love one another, to love one another sincerely. They are to love in a way that they are not conscious of doing wrong.
The sentiment here echoes things elsewhere in Paul, even if his writings never put it quite this way elsewhere. Romans 13:10 and Galatians 5:14 indicate that love is the fulfillment of the Law. In Romans 14:23, Paul describes sin as anything that is not done on the basis of faith.
The false teachers that Paul/1 Timothy has in view have ideas that they connect to the Jewish Law, and they maintain those views strongly. But the perspectives they hold so vehemently are nothing but foolish talk. They have deviated and wandered off course without realizing it.