It is not possible for people to experience and understand all there is about life and its purpose in a single lifetime. By understanding and accepting that we have lived many times before, we are able to develop a sense of the continuity of life - past, present and future. To know that we have lived as both male and female in different areas of the world and have belonged to different racial groups, encourages us to have a more tolerant heart.
We become aware that the choices we made in previous lives are often the cause of our circumstances today and we are better able to deal with the difficulties and suffering in our lives. We also become more appreciative of the blessings and joys we experience in all aspects of our lives - grateful to God for the opportunity to also reap the good that we have sown along with the bad.
Reincarnation also explains the great love and mercy that God has for his children. Consider the infant who dies at birth, or the child born with mental or physical handicaps.
Think of all the young men and women killed in wars and accidents. Surely, they are part of a greater plan that allows them the opportunity to be born again and to live full lives in order to develop and share their unique gifts and talents with humanity.
Just because we cannot remember our previous lives, does not mean we didn't have them. Many people have deja vu experiences where they suddenly and seemingly out of nowhere feel that they have done something before, been somewhere before, or feel that they know someone who they have just met. Many of us have also heard or know children who were born with a special gift in music or science, who became professionals at an early age. This is often an indication that the soul has picked up where it left off from a previous life, bringing with it talents and skills that are part of its service to mankind - its reason for being.
A lot of people have dreams that are set in different time periods, where everyone in the dream is wearing clothing that was worn in previous centuries and where building and towns are completely different from the present life. Dreams like this can mean that your soul is working out unresolved issues from a previous life that may have to do with a current life situation that may be causing you problems.
Along with giving us a better understanding of our life's purpose, reincarnation makes sense out of the law of karma, known as the law of cause and effect, or, as the Bible states. "whatsoever a man soweth, that shall he also reap." Karma is like a personal boomerang - everything that we send out returns to us, for better or for worse. It would be impossible for us to "reap what we have sown" in one lifetime. If we understand reincarnation and the fact that we are responsible for our past and present actions, we become more inclined to think before we react when faced with the difficult situations. We may also become more inclined to forgive and forget those who have wronged us and ask for forgiveness from those whom we have wronged.