There is no way to explain it.  Those who meditate eventually will realize that I am I, and then they will know that I am I, eternally and immortally.  Whether or not they remember past experiences is of absolutely no importance.  You, at this particular minute, probably do not know any of your past experiences, and may never even have thought that you had them. On the other hand, there are those who, through spiritual development, are made aware of their past experience – and yet, not necessarily of all of the experiences of the past, but probably the experience of one particular lifetime, or two or three or four, as the occasion may require.  Now, as a person develops spiritually, and a spiritual work is given them to do, they are provided with everything necessary for their experience, and if it is necessary for them to know something of their past experience, or the why and wherefore of their present experience, it is revealed to them. [...]