The Dhamma which we are trying to acquire during our practice is in fact within us, but we usually do not realize that we have already attained that state and have actually gone past it. Because we do not understand this, we believe that the goal is not reached and so we aim to attain that state sometime in the future. We do not see that if we can know our present state of mind, and are in control of it, then we have already attained it. Nevertheless, if we keep practising, we will still reap the benefit.
We should not hope to engage in difficult practices in the future, because Nibbana is not ahead of us. Nibbana is where our mind is calm and happy. Nibbana is when the mind is aware of its present state.