It may have crossed the line twice, but firing at and killing several assailants while doing his special oil check on the lady in the motel AND drinking scotch was nothing short of side-splitting.
This is also hilarious later on when the shell-shocked waitress is trying to explain what happened to the cops.
The Accountant's very first line in the film.
The Accountant: You, fat fuck.
When the first stoner reacts to him bursting from his overturned car.
Teen #1: Jesus!
The Accountant:Carpenter. And, despite what you've heard, prefers short hair.
And when he is addressing the two stoners.
Teen #2: You almost fucking killed me, man!
The Accountant: Not even close. I won't see you again until you're 73. (looks over at the other guy) You I'll see in three months.
(he walks away)
Teen #1: What does that mean?!
This exchange between the Accountant and one of the cultists after the former notices the latter's pentagram tattoo:
Accountant: What's that?
Cultist: A symbol of our pact with Lord Satan.
Accountant: A pact, huh? Funny — he's never mentioned you.
(looks at the Cultist's shattered legs)
Accountant: Whoa, those are fucked!
After the Accountant interrupts the police trying to apprehend Milton and Piper (thereby allowing them to escape), he whips out his coin, tosses it and it becomes a FBI badge which he shows to the police captain, and we get this exchange:
Captain: No goddamn way! Ain't no goddamn way in God's good heaven are you an FBI agent!
Accountant: Gentlemen, I need you boys to stand down. Captain, you know what this badge means, right? Federal Bureau of Get-the-Fuck-Out-of-My-Way! You boys just stumbled onto an ongoing investigation.
The Accountant then exposes one of the cops as a cultist working for King and tells him to call him. When the cop/cultist does, the Accountant leans in close to hear.
"If your definition of 'forever' is the next five seconds, then you'd probably be right."
The Accountant's reaction when Piper gets free and grabs the Godkiller.