I think using the term 'Past Lives' is a human thing, in a world where we have clocks and have past, present and future. Spirit doesn't have the same concept of time, so in that sense to Spirit there is no past, present nor future. Parallel Lives make more sense to me. When I've gone through 'Past Lives' they don't feel like memories, they feel like those thoughts come from a different part of me, inside.

Karma in terms of good and bad just don't work for me, that smacks too much of judgement. Looking at karma in terms of cause and effect does though.

The way I see it, those 'Past Lives' are happening right now but in a dimension I can't perceive with human senses. It's like a radio station, you listen to one station because that's the one it's tuned into. Turn the dial a tad off-station and you begin to lose the clarity. Turn it a little more and all you get is static noise. A little bit yet and the next station starts to come through. That is where the awareness of 'Past Lives' comes from, because your consciousness is able to tune itself a little, just enough to get past the station you're currently listening to and through a little static into another station.