A spell's power often depends on its caster level, which for most spellcasting characters is equal to your class level in the class you're using to cast the spell.
You can cast a spell at a lower caster level than normal, but the caster level you choose must be high enough for you to cast the spell in question, and all level-dependent features must be based on the same caster level.
In the event that a class feature, domain granted power, or other special ability
provides an adjustment to your caster level, that adjustment applies not only to effects based on caster level (such as range, duration, and damage
dealt) but also to your caster level check to overcome your target's spell resistance
and to the caster level used in dispel checks (both the dispel check and the DC of the check).