If the spell is on your class’s spell list but of a higher level than you can normally cast, you must make an ability check using your Spellcasting ability to determine whether you cast it successfully. The DC equals 10 + the spell’s level. On a failed check, the spell disappears from the scroll with no other Effect.
Notably, the check made is an ability check using your Spellcasting ability (doesn't include Proficiency), not an Arcana/Religion check.
Edit for clarity: I'm just posting this ^ as a reference to exactly what 5e rules say about casting spell scrolls of a level you can't normally cast, since there was a question about the 5e rules above in the thread.
