When you practice yoga you embark on a jedi mind training that teaches you how not to get so caught up in past experience that your future is absolutely determined by it -- while at the same time using your real world experiences to teach you both on and off the mat.
Yoga asks you to reflect on the past as a learning device, not as an absolute future determinant. It would be naive simply to say that there is no past and no future without a firm understanding of just how to live in the present moment. The epiphany moment that wipes away painful past experiences and opens the door to a new way of being happens in one instant and is the culmination of many years of hard work and determination. This moment of transformation is grounded in the past while reaching toward the future and yet must happen in the “now.” Growth often manifests with seeming light speed but this effervescence is actually dependent on years of learning spent on the tight tope between past, present and future.
My teacher, Sri K. Pattahbi Jois often talked about “samskaras”, negative thought forms and mental images that have an uncanny way of determining what our life experience will be, most often for the worse. One of yoga’s most powerful tools is its ability to condense life learning into more easily digestible fragments. If you have an image of yourself as a weak person who needs to work on strength then every time you start your practice you will look for evidence that you are indeed weak. But if you change your mental image, or samskara, of yourself from a weakling to someone who is in the process of building strength you are already creating the change you want. If you see yourself as you have always known yourself to be it is simultaneously something reliable and restricting. If you allow yourself simply to not know who you are in each moment it becomes more possible to give yourself space to discover who you really are underneath all the samkaras created in the past.
It is possible to change samskaras because the depth level of human nature is an eternal, changeless peace that defies all definition that is beyond the products of the past. Culture, family, history and the habit pattern of the mind form the pieces of our personality, but are not who we at the essence of our being. When you believe the externalities of life to be your essence you see them as eternal when in reality these aspects of the self are only temporal. Yoga teaches you how to truly be free from the past just enough so that you can actively choose your future, breathe by breath, posture by posture. Yoga asks you to know yourself deeply not so that you are chained by that knowledge to always be the same as you have always been. Instead the part of yourself that yoga asks you to know is beyond any constructs of time, past or future, and lives only in the present moment. Along the way you must get intimate with the parts of yourself that are transcendent of time so that you can be as you really are, infinite and totally present.