There are many stages to enlightenment. Bhagavan refers to enlightenment as making a hole in the wall of the mind, a wall that keeps us separate from the direct experience of divinity. Making the initial hole is the first step in the journey of enlightenment. The larger the hole, the deeper the state of oneness that we experience. When the wall disappears completely, there is no longer any separation between oneself, nature, creation, and God.
For some, like Ramana Maharshi, the wall is completely obliterated in a moment of time. For most people, however, it is a more gradual process. If the wall is broken down all at once it becomes difficult for the person to function in the normal world, and so in the majority of cases, a slower process is required. A small hole appears, which widens in time as the physical body adjusts to the shifts in energy and perception.