Well, I know that there was at least one flashback in the comics where little!Matt beat up some of his bullies and went home and told Jack about it. Jack had always wanted him to study instead of fighting so that he wouldn't end up like him, and he had been drinking that day, so he got angry...and hit Matt. He realized what he did right away and apologized for it, but Matt was scared and ran. He spent some time alone thinking, and that was when Matt decided to become a lawyer.
The thing about this is that it's horrible and shocking and I don't think anybody really wants to think about it...but it really does make a lot of sense for Matt's character and paradoxical opinion of violence.
Now, that hardly matches the level of violence Matt was describing in the confessional scene, and who knows if the show's version of Jack Murdock would ever have done something like this. But there is at least some evidence in the comics for what (I think) you're implying.
Re: episode one confessional
The thing about this is that it's horrible and shocking and I don't think anybody really wants to think about it...but it really does make a lot of sense for Matt's character and paradoxical opinion of violence.
Now, that hardly matches the level of violence Matt was describing in the confessional scene, and who knows if the show's version of Jack Murdock would ever have done something like this. But there is at least some evidence in the comics for what (I think) you're implying.