You can change jobs to a Knight in the Capital City of Prontera. Apply at the Prontera Chivalry, located in the 11 o'clock direction. Turn in your application to the Captain and you will be instructed to talk to each member. The job change process tests compassion, bravery, insight, and loyalty. You must be exeperienced and knowledgable to pass this test. The Captain will then evaluate the results and you will be able to change to a Knight afterwards. Requirements are Job Lv 40.