[quote=@Prince of Seraphs]
<Snipped quote by Lugubrious>

<Snipped quote by Kafka Komedy>

But it doesn't have an external source like in Guilty Gear or some of the Final Fantasy games such as a God of Magic or some form of other realm.

In Bravely Default for instance wasn't there a pillar of pure magical energy that Kaiser tapped into for time travel.
[/quote]

No, there is no special source for magic in FE.