“I always thought love made you stupid. Made you weak. A bad Shadowhunter. 'To love is to destroy.'I believed that[...]I used to think being a good warrior meant not caring,[...] And then I met you. You were a mundane. Weak. Not a fighter. Never trained[...] Love didn't make you weak, it made you stronger than anyone I'd ever met. And I realized I was the one who was weak.”

“I used to think being a good warrior meant not caring,” he said. “About anything, myself especially. I took every risk I could. I flung myself in the path of demons. I think I gave Alec a complex about what kind of fighter he was, just because he wanted to live.” Jace smiled unevenly. “And then I met you. You were a mundane. Weak. Not a fighter. Never trained. And then I saw how much you loved your mother, loved Simon, and how you’d walk into hell to save them. You did walk into that vampire hotel. Shadowhunters with a decade of experience wouldn’t have tried that. Love didn’t make you weak, it made you stronger than anyone I’d ever met. And I realized I was the one who was weak.” –Jace pg. 531-532”

“Love didn't make you weak, it made you stronger.”

“Mort was already aware that love made you feel hot and cold and cruel and weak, but he hadn't realized that it could make you stupid.”

“She realised with an intense, wonderful rush that love didn't make you weak. It made you vulnerable, but it also made you strong.”

“That was the problem with loving people: it made you weak. It made you need them. It made the thought of not having them the worst thing in the world.”