Divine Vestments

With a brief prayer, you are able to imbue your person with divine protection, and cloaking yourself in barely visible golden aura. While the spell lasts, your AC equals 15 + your Dexterity modifier while not wearing any other armor, or carrying a shield. 

At Higher levels. When you cast this spell using a spell slot of 3rd or 4th level, this spell lasts for 8 hours. If you use a spell slot of 5th level or higher, it instead lasts for 24 hours.