2 days had passed since Damien witnessed the benefits of the Void Heart Sword Law. For the past two days, he had done nothing but sit in a meditative position with his eyes closed.
After expressing his desire to practice the sword law, he was sent back to his real body from the void space he was transported to. The emotionless voice he had heard said nothing else to him.
But it wasn't without benefit. When his mind returned to his body, he could feel an immense wave of information imprinting itself onto his consciousness.
The Void Heart Sword Law actually wasn't very difficult to learn in theory. The main caveat of the art was the user's capability at emptying their mind of all emotion. Without passing this first step, it was impossible to practice the art.
And even in these past 2 days, Damien wasn't able to complete this step.