There is an analogy here about name and form.

Consider the space. There is an empty jar in space. The space inside the empty jar is in no way different from the space outside the empty jar. But the space inside the empty jar is a subset of space. Why is it a subset? Because of the constraining nature of the jar itself. Now if the jar is destroyed then we cannot differentiate the space that was formerly inside the jar and the one that was outside. The jar is like a name or a form which is trying to bind the space inside. The name and form are a result of maya. When this maya is destroyed, then the realization that the Atman is the Brahman truely dawns on us.