Jerry Nadler: AG William Barr won't testify because he is 'terrified' to answer our questions

AG William Barr has opted not to testify before the House Judiciary Committee on Thursday. House Judiciary Committee Chairman Nadler says the panel would "start a process" to get Barr to testify, and says the next step is a contempt citation.

So Democratic Judiciary Committee chair Jerry Nadler responded to Barr saying that he wasn’t goint to show up tomorrow.
He is threatening to hold Barr in contempt:
 House Judiciary Chairman Jerry Nadler says if Attorney General William Barr doesn't provide the unredacted Mueller report to Congress in the next day or two, "the next step is seeking a contempt citation against the attorney general"
However, when it came to hitting Barr with a subpoena, Nadler was non-committal about it.

So, it’s kind of a showdown. Will Barr back down and show up? It sounds like Nadler will give him a few days to consider. But they can then hold him in contempt, and if that doesn’t work, hit him with another subpoena. But if he ignores that…. then what?