All monks have trained their spirit to the point that it can be used as a minor buffer against attacks. The tradition you have adhered to is focused entirely on bolstering one's spirit guard beyond conventional limits. With an aura of Ki so dense it can almost be seen, you will be able to lessen the impact of any weapon that manages to make contact with you or turn that surplus of energy back into yourself to help rejuvenate yourself.

Ki Armor

Starting when you choose this tradition at 3rd level, when you let your ki flow in the heat of battle, a portion of the ki temporarily cloaks your body in a protective aura.

Bludgeoning, piercing, and slashing damage you take from nonmagical weapons is reduced by 2.

Whenever you expend a ki point you gain resistance to bludgeoning, piercing, and slashing damage from nonmagical sources until the start of your next turn. If multiple points were spent in a single round, the resistance lasts for a number of extra rounds equal to the points spent. 

Starting at 6th level, the damage reduction and resistance granted by this ability are also effective against magical sources.

Rejuvenation

Beginning at 6th level, at the start of your turn, if you received no damage while your damage resistance from Ki Armor was active you can roll your martial arts die and regain hit points equal to the number rolled.

Ward of Mind and Spirit

At 11th level, your resilient Ki can help protect you from attacks no just from weapons, but also those targeting your inner self. When you are targeted by a spell, you can spend 1 ki point as a reaction to give yourself advantage on Charisma, Intelligence, and Wisdom saving throws against the initial cast.

Reverberations

By 17th level, your Ki is able to store some of the force it absorbed from attacks. Whenever Ki Armor reduces your damage taken, keep track of how much damage you avoided (both from the damage reduction and resistance). You can store an amount of damage equal to your monk level. On your turn, when you hit a creature with an unarmed strike, you can release the pooled damage. You can either increase the damage of the unarmed strike by the amount you had pooled, or regain hit point equal to half that amount (rounded down).