Celestial Conduit

You become a conduit for celestial energy, enveloped in radiant light. For the duration, you gain the following benefits: You emit bright light in a 20-foot radius and dim light for another 20 feet. You have resistance to necrotic damage. When you or an ally within 10 feet of you takes damage, you can use your reaction to reduce that damage by 1d8 + your spellcasting modifier.