He outright lied about a couple of things, like when he was asked by Holt about Mueller's claim in his letter to Barr, that Barr's summary of his investigation did not address, among other things, the substance of the investigation.
Barr denied Mueller said that, even though it is there in black and white for everyone to see.
He also claimed that he didn't feel anything punishable occurred when Trump tried to pressure Zelensky into launching or just announcing, an investigation into Hunter Biden in exchange for the foreign aid which Congress had already approved.
He basically just made excuses for his whitewashing of Trump's crimes and treason.
The only things he seemed to be honest and forthcoming about, was Trump's childishness and his lack of mental and psychological fitness for office.