Sriamate Ramnujaye Namaha!

Namaskaaram, swami.

My understanding as per what i have heard is 

Protection is ways and means by which Perumaal  helps to preserve and grow – sat vishayangal in us, like good qualities, kainkaryam,etc and other basic necessities that are required to do our service (like maintaining the body etc) . ( It is like putting a fence around creeper of devotional plant and giving sunlight, water and necessary manure)

Punishment is also for protection but by removing unnecessary things we have – bad qualities/bad desires etc..( it is like removing weeds from around the plants, cutting infected parts of a plant etc..)

adiyen.