In Red Robin 22 It says that Tim has no sins and nothing to repent for. Does that seem a little weird to anyone else? He is one of my favorite characters, but I am a firm believer in no one is perfect. He is a very good person and tries to help people, but he still makes mistakes and sometimes he also will do a bad thing for a good reason (ex. lying to his dad to keep his and Batman's identities secret.) 

lol now i want to buy that issue

Also i thought Dick was the one that ended up being sinless? Tim has done some cruel and inhumane sh!t since he became Red Robin

He probably doesn't believe in the concept of "sin" as a state, since he is an athiest (or agnostic), so he probably doesn't hold any of the guilt associated with sin. And he really has done his utmost to be morally right in all of his actions. I can believe a sword like Azraels wouldn't find a problem with him. It would detect neither moral wrongdoing in Tim's past (nothing to atone for) or any feelings of pent-up "sinfulness" since he doesn't believe in that stuff. 
 
As for any day-to-day stuff--"thou shall not covet thy brother's batmobile"--I'd say a "tickle" from the sword covers that.