Alec Lightwood (to Magnus): Jace is a part of me. Through a rune, we are both physically and emotionally connected. If he dies, a part of me dies, too. And I know he’s out there. And he’s in trouble, and there’s not a damn thing I can do about it.
From Shadowhunters – Season 2 Episode 1: ‘This Guilty Blood’ (2×01)