"...Church's fine," the older girl says warily after a moment. 

"I can only carry one person at a time."

This is probably going to be the point where they're most wary, and that's entirely reasonable.There's evil wizards out there too.

"If it helps, I can do the whole trip in smaller jumps from roof to roof. It'll be slower, but that way no one is ever out of sight."

She nods tightly. 

Over several short trips, they are all carried to the doors of the temple. Knocking on the door, he has a quiet conversation. (Explaining the situation, promising a hefty donation when he comes back in a few weeks and likes what he sees, threatening that if they're mistreated or separated from each other then he has wizard ways of finding out, that kind of thing.)

Then back to the kids. "This is where I fly away, but first, if any of you want to tell me your names, you can. Do not do this unless you want a wizard to be aware of your existence specifically."

He's probably not going to do anything with the information except check back in later on how they're doing. Unless he does something else on a whim like, in ten years, sending one to a non-cheliax wizard school. But still, you shouldn't become an patron who watches someone's potential and occasionally intervenes in someone's life without asking that person first. 

The children stare at him for a moment where they're all huddled together, before the tiefling says, "Arhan!" 

The older girl gives him a reproachful look. He crosses his arms defiantly. "It's not like I'm going to be safe if I just keep my head down and don't take any chances." 

Some people try to make it to archmage or die trying. Some people try to live safe happy lives. 

"Good choice. Both of you."

Once they're safely inside and out of the rain, he's back in the air.