A hard concept to get right. Since this is a top-down design (the concept came first, the mechanics later) it's important to really flesh out what the card represents, and how that fits into Holy school.
Does it blind? Can you see through it? What conditions would it interact with, if any? Is it fragile? Temporary? Dangerous? Does it fly? etc. etc.
How I see it:
A holy light-wall, nearly invisible. Maybe as if the sun shines brighter just on that line. It does not block line of sight. Ranged magical attacks are blocked by it. (so no fireball can hit something behind it) Zone attacks CAN go trough. (firestorm behind the wall is no problem)
But when creatures move trough it, Asyra will aid her followers or punish the evil creatures. Magical attacks are stopped, and shatter on the wall because Asyra wants to protect her holy priestess and temples.
mana cost&level: ? based on play-testing
incorporeal (health based on mana cost/testing/...) could be both fragile as strong
healing: 2 dice
damage: 3 dice direct damage, 7+ daze, 10+stun
Conditions: None or same as any other incorporeal conjuration
flying?: maybe both flying as non-flying? (covering everything)