According to the Gears of War novels, all COGs must take this oath:
"I shall remain vigilant and unyielding in my pursuit of the enemies of the Coalition. I will defend and maintain the order of life as it was proclaimed by the Allfathers of the Coalition in the Octus Cannon. I will forsake the life I had before so I may perform my duty as long as I am needed. Steadfast, I shall hold my place in the machine and acknowledge my place in the Coalition. I am a Gear. "