Dreaming about taking an oath signifies holding oneself to a commitment. It asks for discipline, which might appear unrealistic in your waking life if you are currently unmotivated and stuck in a phase of little personal growth. It implies the actions we must take, to be the better person we could become.
People who swear their commitment with the help of an oath, tend to do better with a reminder to not engage in any activity contrary to the values represented by the oaths.