[ Maybe it's a sixth sense of being a spirit or maybe Jack just makes a good guess, but he doesn't miss the rising anxiety. ]

Hey... I don't know what kind of reaction you've got in the past but-- you're not going to get it from me. This doesn't change the person I've gotten to know.

[ Admittedly "gotten to know" is a bit of a stretch, because Costigan has always been tightlipped about himself. The few instances where he'd shared personal information with Jack were significant but infrequent, making the spirit recognize them with that much more importance. ]