Play goes like this:
For this creature I pay its madness cost and place it on the field.
Does Faith of the Devoted's ability trigger?
What confuses me is what this page on the Discard keyword says:
Discard is an evergreen keyword action which takes cards from a player's hand and puts them in their graveyard.
But the fact is that a creature with madness never hits the graveyard! Instead, it goes to exile, then to the battlefield.
So I'm not completely sure whether the discard ability on Faith of the Devoted should trigger on that.