It’s interesting that in focusing on breathing, you realise that breathing is something objective, it is a fact. Having thoughts which are related to the past and the future can generate unpleasant emotions, but with the help of focusing on breathing you can learn to let go of the past and let go of the future and experience the joy and the bliss of the present moment.
This reminds me of an incident which is recorded in the Buddhists texts, in the Buddha’s time – a non-Buddhist visits a monastery where meditating monks are living, and this person was very impressed, very inspired by the serenity of the monks, by the way they were relaxed and joyful in their behaviour. So he goes to the Buddha and asks him: Pray tell me what you teach your disciples?.
Then the Buddha said: I teach them not to worry about the past, because it is gone; and not to be anxious about the future because it is yet to come – rather to experience the joy of the present moment. And with that they have been able to exude this joy, peace and compassion in their behaviour.
Now living in the present can raise a question: is it possible always to live in the present? What about planning? What about using the past? If you let go of the past you will not be able to find your homes, you will not be able to use language, you will not be able to recognize anything. So what is meant here, what one has to experience, is that with this process of recalling and anticipating you do it now. This is a very important point for one to experience and realise, that what is considered as the past is just a thought in the present, and what is considered the future is also just a thought in the present. So when you realise this, when you experience this, you will be able to relate to the past and the future in an entirely different way, where you can use the past and the future functionally and not allow the past and the future, in this process of recalling and anticipating to generate unpleasant emotions which create our suffering.