Divine light washes out from you and coalesces in a soft radiance in a 30-foot radius around you. Creatures of your choice in that radius when you cast this spell shed dim light in a 5-foot radius and have advantage on all saving throws, and other creatures have disadvantage on attack rolls against them until the spell ends. In addition, when a fiend or an undead hits an affected creature with a melee attack, the aura flashes with brilliant light. The attacker must succeed on a Constitution saving throw or be blinded until the spell ends.
You can find more information on this spell in: PHB.251