Lan Wangji knows that Magnus is strong, quick of mind and body, and capable. He has witnessed that, and felt it for himself in the force with which they can embrace one another. If the universe here ordered itself as it should, as he is accustomed to it doing, he could rest easily with full faith in him. Here, though, there are unidentifiable shadows in the night, a tempestuous emperor who could poison the blood of half the mansion with a well-placed drop of his own if he willed it, ill-intended swords that strike with no master in sight.

Magnus says that Lan Wangji's protection is worth a lot. Lan Wangji is not so certain, but he holds Magnus, and doesn't falter, and waits patiently for him to feel able to face the world outside of Lan Wangji's arms.