Spell Holding

Hello Everyone,

So I was reading Spell Holding and I'm confused on what exactly it means. Does It allow a character to choose a spell she knows and use it like a periodic skill for an encounter, being able to invoke it at will for the duration of the encounter, or does it simply allow a character to use one non-prepared spell she has, cast it as a prepared spell, then invoke it at a later time as per the prepared rule? Or does it work some other way that I'm missing?

I posted the Rules for Spell Holding and the rules on prepared below for ease

Thank you,

-Austin

Spell Holding
This ability allows the character to choose
one spell she is capable of casting. For the
duration of the encounter, she may cast the
spell as a ​Prepared​ ability.
Continuous

Prepared ​– The ability must be performed
by the character ahead of time and held in
reserve until she chooses to invoke it.
Prepared abilities expire after five minutes
unless the character concentrates on
maintaining them; the concentration is
instantly broken and may not be resumed if
she takes any action other than speaking or
moving

Spell Holding allows the character to take a non-Prepared spell and cast it using the Prepared rules. For example if you use Spell Holding with Enigmatic Lance, you spend your casting time ahead of time and then hold it in reserve as Prepared. You may then instantly activate it following the Prepared rules. Once you use it, you would need to spend the five seconds ahead of time to Prepare it before you can use it again.