I have a templar who is 5. I've been using the first Radiant Light healing spell for the past 4 hours to heal myself and others and it's still Level 1. Whereas the second healing spell (don't remember the name) is level III, and I barely used it.
I have the same issue with my soul magic spell. I've been tagging mobs with it, since it has a DoT, and have used it to fill soul gems, but it's barely level 1 (just the tip of the blue advancement arrow showing)
Are there certain conditions that have to be met for spells to advance?