I have always wondered how long does it take for one to remember a past life in a sitting, an immediate previous life for example, does it take just a few minutes, or hours or maybe days?
This answer briefed the following way to remember past lives:
Obtain the four rūpa-jhānas.
Exit the fourth jhāna and remember the last thing one did before one sat down.
Remember the last thing before the thing remembered in the last step. If at any time, one is unable to remember a given experience, one should revert to step one, and after leaving the fourth jhāna attempt to continue where one left off.
Repeat step 3 until one is able to remember the first moment of conception.
Attempt to remember the last moment before conception (i.e. the death moment).
Look at step 3, you have to remember the previous thing, and previous, and previous... Wow, how long would it take? Do we need to skip some huge steps (maybe 10 years of one's childhood) ? Or maybe the mind work lightningly faster when you are in that recollecting mode?