The next step - concentration - implies steadiness of mind. You cannot concentrate until you have made the external part steady. Just think! Can you keep your eye in one place for a few moments, without moving it? Can you sit in one posture without fidgeting? Why, you cannot sit still even for a photographer. This shows us that the vehicle given us to control and utilize is not completely in our power. If the lowest vehicle we have is not in our power, though this is the simplest thing to control, how can our mind be in our control? How can we acquire more pure and more powerful thoughts?