The Master says, If you have not developed your memory, you are not really educated.
What is the real meaning of undeveloped memory? Yogananda tells us memory gives us the power to recollect our past experiences and we were given memory so as not to forget specific experiences and consequently neglect to learn the valuable lessons they teach. All the events, experiences and reactions you have had since your early childhood are all squirreled away in your subconscious mind. Therefore you benefit from those that include indispensable lessons and reject the rest. We cannot benefit from an event if the experience has been forgotten.
There are different ways to develop a good memory. Pay strict attention to what has to be remembered. The strongest force to develop memory is deep attention. Why do people remember the major sorrows of their lives? The master tells us they have directed more attention to them. An inferior memory usually signifies a mind that jumps from one point of thought to another without concentrating on each separate thing. Different people have different degrees of active memory corresponding to their mental ability. Thus according to their brain capacity some are able to remember more than others. You need concentration, experiences, meditation and education in order to develop your memory. A person is not really educated unless he has developed his memory.
Most individuals are born with a certain amount of memory ability. There are special exercises one may use to develop memory. You limit your soul by failing to exercise this ability in a broader way. Discipline is very important when exercising memory. We can stretch our memory like rubber and being elastic and eternal if developed can record many things. Do you remember what you did a week ago today? Try to recall every day what you previously did a week ago. Try to visualize or remember some event, place or object. Mentally practice mathematics like adding, subtracting and multiplying.